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John Baez

John Baez 

Occupation: I'm a mathematical physicist. (Centre for Quantum Technologies)

Location: Riverside, California

Followers: 57,575

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Views: 50,969,065

Cream of the Crop: 11/05/2011

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Most comments: 153

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2016-05-30 16:00:05 (153 comments; 113 reshares; 332 +1s; )Open 

Let us read what we paid for

Imagine a business like this: you get highly trained experts to give you their research for free... and then you sell it back to them.  Of course these experts need equipment, and they need to earn a living... so you get taxpayers to foot the bill.  

And if the taxpayers want to actually read the papers they paid for?   Then you charge them a big fee!

It's not surprising that with this business model, big publishers are getting rich while libraries go broke.  Reed-Elsevier has a 37% profit margin!

But people are starting to fight back — from governments to energetic students like ‎Alexandra Elbakyan here.

On Friday, the Competitiveness Council —a gathering of European ministers of science, innovation, trade, and industry—said that by 2020, all publicly funded scientific papers published in Europeshould be ma... more »

Most reshares: 113

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2016-05-30 16:00:05 (153 comments; 113 reshares; 332 +1s; )Open 

Let us read what we paid for

Imagine a business like this: you get highly trained experts to give you their research for free... and then you sell it back to them.  Of course these experts need equipment, and they need to earn a living... so you get taxpayers to foot the bill.  

And if the taxpayers want to actually read the papers they paid for?   Then you charge them a big fee!

It's not surprising that with this business model, big publishers are getting rich while libraries go broke.  Reed-Elsevier has a 37% profit margin!

But people are starting to fight back — from governments to energetic students like ‎Alexandra Elbakyan here.

On Friday, the Competitiveness Council —a gathering of European ministers of science, innovation, trade, and industry—said that by 2020, all publicly funded scientific papers published in Europeshould be ma... more »

Most plusones: 332

posted image

2016-05-30 16:00:05 (153 comments; 113 reshares; 332 +1s; )Open 

Let us read what we paid for

Imagine a business like this: you get highly trained experts to give you their research for free... and then you sell it back to them.  Of course these experts need equipment, and they need to earn a living... so you get taxpayers to foot the bill.  

And if the taxpayers want to actually read the papers they paid for?   Then you charge them a big fee!

It's not surprising that with this business model, big publishers are getting rich while libraries go broke.  Reed-Elsevier has a 37% profit margin!

But people are starting to fight back — from governments to energetic students like ‎Alexandra Elbakyan here.

On Friday, the Competitiveness Council —a gathering of European ministers of science, innovation, trade, and industry—said that by 2020, all publicly funded scientific papers published in Europeshould be ma... more »

Latest 50 posts

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2016-08-27 04:43:12 (21 comments; 12 reshares; 94 +1s; )Open 

Dark mysteries

You probably heard the news this week: astronomers found a galaxy that's 98% dark matter. 

It's called Dragonfly 44.  It's extremely faint, so it doesn't have many stars.   But we can use redshifts to see how fast those stars are moving - over 40 kilometers per second on average.  If you do some calculations, you can see this galaxy would fly apart unless there's a lot of invisible matter providing enough gravity to hold it together.   (Or unless something even weirder is happening.)

Something similar is true for most galaxies, including ours.   What makes Dragonfly 44 special is that 98 percent of the matter must be invisible.   And this is just in the part where we see stars.   If we count the outer edges of the galaxy, the halo, the percentage could rise to 99% or more! 

By comparison, theMilky Way is... more »

Dark mysteries

You probably heard the news this week: astronomers found a galaxy that's 98% dark matter. 

It's called Dragonfly 44.  It's extremely faint, so it doesn't have many stars.   But we can use redshifts to see how fast those stars are moving - over 40 kilometers per second on average.  If you do some calculations, you can see this galaxy would fly apart unless there's a lot of invisible matter providing enough gravity to hold it together.   (Or unless something even weirder is happening.)

Something similar is true for most galaxies, including ours.   What makes Dragonfly 44 special is that 98 percent of the matter must be invisible.   And this is just in the part where we see stars.   If we count the outer edges of the galaxy, the halo, the percentage could rise to 99% or more! 

By comparison, the Milky Way is roughly 90% dark matter if you count the halo.  We know this pretty well, because we can see a few stars out in there and measure how fast they're moving.

There are also galaxies like NGC 3379 that may have less than the average amount of dark matter in their halo, though this is debatable.

And most excitingly, sometimes clusters of galaxies collide and stop moving, but their dark matter keeps on going! 

We can see this because light from more distant galaxies is bent, not toward the colliding clusters, but toward something else.   The most famous example is the Bullet Cluster, but there are others.

All these discoveries - and more - make dark matter seem more and more like a real thing.  So it's more and more frustrating that we don't know what it is.  As I explained a while ago, recent experiments to detect particles of dark matter have failed.  So it could be something else, like black holes about 30 solar masses in size.  And intriguingly, the first black hole collision seen by LIGO involved a 35-solar-mass and a 30-solar-mass black hole.  These are too big to have formed from the collapse of a single star.  They might be primordial black holes, left over from the early Universe.

But more on that later.

For more on Dragonfly 44, see:

• Pieter van Dokkum, Roberto Abraham, Jean Brodie, Charlie Conroy, Shany Danieli, Allison Merritt, Lamiya Mowla, Aaron Romanowsky and Jielai Zhang, A high stellar velocity dispersion and ~100 globular clusters for the ultra diffuse galaxy Dragonfly 44, http://arxiv.org/abs/1606.06291.

For our failure to find dark matter particles, see this post of mine:

https://plus.google.com/117663015413546257905/posts/3U53iqtWYXk

For more on dark matter on the outer edges of galaxies, see:

https://en.wikipedia.org/wiki/Dark_matter_halo

For the Milky Way's dark matter halo, see:

• G. Battaglia et al, The radial velocity dispersion profile of the Galactic halo: constraining the density profile of the dark halo of the Milky Way, http://arxiv.org/abs/astro-ph/0506102

#astronomy___

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2016-08-26 05:35:36 (26 comments; 18 reshares; 93 +1s; )Open 

The driverless taxi is here

Singapore now has the world's first driverless taxi! 

Yes, just one so far.  Only 10 people are allowed to use it, and it will stay in the most futuristic part of town, near the research centers Biopolis and Fusionopolis.  But the company nuTonomy hopes to make this service commercially available by 2018, with a fleet of 75 cabs.  And it wants to boost the number to thousands by 2019.

Singapore just barely beat Pittsburgh: Uber plans to offer driverless rides there in a few weeks.

Here's a story from May 2016:

During this test drive, there were people; there was construction; there was even a fairly busy intersection.

Being able to understand traffic lights, navigate to a destination and not just detect obstacles but figure out when and how to pass them is no small feat for anaut... more »

The driverless taxi is here

Singapore now has the world's first driverless taxi! 

Yes, just one so far.  Only 10 people are allowed to use it, and it will stay in the most futuristic part of town, near the research centers Biopolis and Fusionopolis.  But the company nuTonomy hopes to make this service commercially available by 2018, with a fleet of 75 cabs.  And it wants to boost the number to thousands by 2019.

Singapore just barely beat Pittsburgh: Uber plans to offer driverless rides there in a few weeks.

Here's a story from May 2016:

During this test drive, there were people; there was construction; there was even a fairly busy intersection.

Being able to understand traffic lights, navigate to a destination and not just detect obstacles but figure out when and how to pass them is no small feat for an autonomous vehicle. Often, that clumsiness was simply a result of the vehicle being overly careful and leaving considerable space between it and the object it was skirting.

Determining when it's safe to overtake a stopped car is a significant challenge for autonomous cars. Many of today's semi and fully autonomous systems, which depend largely on vehicles around them to determine how fast or slowly to drive, would wait patiently behind the car in front of it until it moved. But nuTonomy cars use formal logic, Parker said.

"Essentially, we establish a hierarchy of rules and break the least important," he said. "For example, one rule is 'maintain speed.' Another is 'stay in lane.' We violate the 'stay in lane' rule because maintaining speed is more important."

At one point during the test drive, the car passed another car that was stopped on the left side of the road. To do that, it veered all the way to the right, then abruptly turned left to overtake the stopped car. Had it been a human driver taking a road test, the maneuver would have resulted in an automatic failure.

Though Parker joked that he was always telling his engineers they could reduce the "buffer space" the car gives other objects or people on the road, that buffer is a necessary safety net when deploying an autonomous car in a complex and unstructured environment.

nuTonomy is an MIT-based startup, and I'm happy they've come here to Singapore.  Here's why, according to the local newspaper:

nuTonomy chief operations officer Doug Parker told The Straits Times that it chose to try out the service in Singapore because of the high consumer demand for taxis here, well-maintained roads and clear government regulations for its tests. "Singapore is the best place in the world for self-driving cars," said Mr Parker.

When you're trying to do new stuff you don't want too many regulations, but it's equally important that the regulations be clear.  You don't want to have to guess whether something is okay.

The first quote is from here:

http://www.recode.net/2016/5/17/11689064/nutonomy-self-driving-car-singapore-test

The second one is from here:

http://www.straitstimes.com/singapore/transport/worlds-first-driverless-taxi-trial-kicks-off-in-singapore

You can see the nuTonomy car in action here:

http://nutonomy.com/___

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2016-08-25 10:03:24 (39 comments; 2 reshares; 41 +1s; )Open 

Transitions

I'm ashamed to say I've never been to a "rave" and danced the night away.   But if I ever do, this is what I want to hear. 

Because I somehow missed this sort of scene - spending my youth more quietly - I'm only now getting into various kinds of electronic dance music that I should have known about a long time ago.   I started with Photek's Modus Operandi, a masterpiece of icy cold, sometimes jazzy, vaguely sinister drum-and-bass.  Then I picked up Richie Hawtin's Consumed, just because I liked the spooky look of this CD, and discovered he too has the mysterious, "chilly" esthetic I often enjoy... though not the virtuosity Photek can muster.  

(I must sound strange.  Though I've become cheerful and romantic in the second half of my life, I'm still extremely fussy about music that acts that way. Why?  I ... more »

Transitions

I'm ashamed to say I've never been to a "rave" and danced the night away.   But if I ever do, this is what I want to hear. 

Because I somehow missed this sort of scene - spending my youth more quietly - I'm only now getting into various kinds of electronic dance music that I should have known about a long time ago.   I started with Photek's Modus Operandi, a masterpiece of icy cold, sometimes jazzy, vaguely sinister drum-and-bass.  Then I picked up Richie Hawtin's Consumed, just because I liked the spooky look of this CD, and discovered he too has the mysterious, "chilly" esthetic I often enjoy... though not the virtuosity Photek can muster.  

(I must sound strange.  Though I've become cheerful and romantic in the second half of my life, I'm still extremely fussy about music that acts that way.  Why?  I guess because most of it feels faked.  There are exceptions, which I treasure.)

Anyway, it was only when I got ahold of Photek's BBC Essential Mix  on YouTube that I started seeking hour-long "mixes" where a DJ blends different dance tunes. 

Unfortunately I'm extremely fussy about these, too, because certain musical cliches make me gag - and let's face it, dance music is mostly cliches repeated over and over for so long that you can't help starting to twitch in synch.  So, I haven't found many that I can tolerate, and if you suggest some, I'll probably hate 'em.   But I've gotten to like stuff by John Digweed.

At first I thought this was a stage name - the perfect name for a stoner DJ - but it's apparently real.  He hails from Hastings in the UK.  Later he became famous for playing sets that lasted between eight and twelve hours at his club Twilo in New York. 

I can completely understand this, because his albums tend to be hour-long solid blocks of energetic music that go on and on and on, slowly morphing and building to a series of climaxes... never very ferocious, much more friendly than guys I just mentioned... but with a huge emphasis on continuity. 

You'll see this here.  Starting very quietly, the music builds to a delirious psychedelic peak at 1:20, then thins to a steady, almost stolid drum beat with bass until 2:22.  Then a cymbal enters, making it sound like things are moving faster (though the beat remains steady), and a simple repeated descending melody enters.  This gradually grows louder and more complex, with an echoed vocal chorus slowly sneaking in... building to another crescendo at 4:58.   And then the music empties out again, leaving us at a quite place similar to where we were back at 2:22, but different.   And then it gradually builds again...

This is undoubtedly less fun to read than to listen to, but I hope you get an idea of the structure, which keeps unfurling in a similar way for an hour, somehow gradually becoming more intense all the time, despite many moments where things quiet and calm down.  I've never listened to a piece of music where there are so many moments where I say to myself "now it's really getting going". 

He is probably making use of some kind of cognitive illusion.  It reminds me of the Shepard tone illusion, where a note seems to rise in pitch endlessly.  Speaking of which, check out +Vi Hart's video about that:

https://www.youtube.com/watch?v=PwFUwXxfZss

But he's doing it much more subtly, more metaphorically, and to better musical effect.   There are certain passages, further along in this long album, where I say now it has finally achieved its full greatness.  And so I'm tempted to recommend jumping straight to 37:00 for the funky, bubbly bounce, 47:00 for the rather ominous blasts of sound, or 1:09:00, where a beat comes in that makes me want this thing to go on all night... but I suspect that would be completely missing the point.  It's not the destination, it's the journey.

Or, you might say: the transitions.

This album, from 2006, is a skillfully blended mix of other people's tunes.  You can see them listed here:

https://en.wikipedia.org/wiki/Transitions_(John_Digweed_album)

Mix tapes had been circulating informally for a long time, but Digweed was the first to officially market one as an album, in 1994. 

#favoritemusic  ___

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2016-08-24 11:38:23 (25 comments; 20 reshares; 135 +1s; )Open 

Quantum cryptography in space

Last week China launched Micius, the first of 20 satellites that will use quantum entanglement to create almost unbreakable codes. 

This satellite will broadcast pairs of photons to two ground stations.  These photons will be entangled - correlated in a way that's only possible through quantum mechanics.  If you share an entangled pair of photons with a friend, you can use them as a key to decode the messages you send each other.   And if someone tries to intercept this key, you can detect it!   No third party can access entangled information without affecting it.

This idea has already been tested over long distances - it's not just a crazy dream.  What's new is sending entangled photons from satellites orbiting the Earth.  China's new system is called QUESS: Quantum Experiments at SpaceScale.<... more »

Quantum cryptography in space

Last week China launched Micius, the first of 20 satellites that will use quantum entanglement to create almost unbreakable codes. 

This satellite will broadcast pairs of photons to two ground stations.  These photons will be entangled - correlated in a way that's only possible through quantum mechanics.  If you share an entangled pair of photons with a friend, you can use them as a key to decode the messages you send each other.   And if someone tries to intercept this key, you can detect it!   No third party can access entangled information without affecting it.

This idea has already been tested over long distances - it's not just a crazy dream.  What's new is sending entangled photons from satellites orbiting the Earth.  China's new system is called QUESS: Quantum Experiments at Space Scale.

Micius will attempt to send entangled photons to the Xinjiang Astronomical Observatory, out in the wild west of China, and an observatory near Beijing – about 2500 kilometers away!

If that works, they'll do it between China and the Institute for Quantum Optics and Quantum Information in Vienna – 7500 kilometers apart.

Later, the QUESS project will try to demonstrate violations of Bell's inequality at a distance of 1,200 kilometers. 

What are "violations of Bell's inequality"?  In very simple terms, it means quantum mechanics is weird.   More precisely, it means quantum mechanics allows correlations that would be impossible if ordinary probability theory were correct.

Then, QUESS will try to teleport a photon state from Tibet to a satellite.  Quantum teleportation is not the teleportation of matter – we're not talking "beam me up, Scotty!"  It's the complete transfer of quantum information from one place to another, which requires destroying the original copy of that information.

If these tests are successful, more satellites will be launched, allowing a European–Asian quantum-encrypted network by 2020, and a global network by 2030. 

Here at the +Centre for Quantum Technologies we've known this future was coming.  Indeed, the director, +Artur Ekert, helped invent quantum cryptography!  But soon this future will be here.

Puzzle: "Micius" is a rarely used romanization of a Chinese name.  You've probably heard of "Confucius", who was really Kong Fuzi.  You may have heard of the philosopher "Mencius", who was really Mengzi.  Who was Micius?  (Googling is easy; knowing things is harder.)

For more, see:

http://www.popsci.com/chinas-quantum-satellite-could-change-cryptography-forever

and

https://en.wikipedia.org/wiki/Quantum_Experiments_at_Space_Scale

which gives away the puzzle.

#physics___

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2016-08-23 14:32:26 (52 comments; 11 reshares; 96 +1s; )Open 

Jump for joy

Dolphins do this.  Why?   Maybe just for fun.  If you've ever seen the amazing games they play with air bubbles, you'll know what I mean.  If you haven't, check this out:

https://plus.google.com/117663015413546257905/posts/W8AAhgY1tCz

It was one of my most popular posts!

But people actually debate this question.  Here's what they say at Dolphins-World :

Why do dolphins jump out of the water?

There is an ongoing debate about why dolphins jump out of the water.  Scientists think about different reasons for this behavior.

Among them, some think that dolphins jump while traveling to save energy as going through the air consume less energy than going through the water.

Some other think that jumping is to get a better view of distant things, mainly food. So, inthis w... more »

Jump for joy

Dolphins do this.  Why?   Maybe just for fun.  If you've ever seen the amazing games they play with air bubbles, you'll know what I mean.  If you haven't, check this out:

https://plus.google.com/117663015413546257905/posts/W8AAhgY1tCz

It was one of my most popular posts!

But people actually debate this question.  Here's what they say at Dolphins-World :

Why do dolphins jump out of the water?

There is an ongoing debate about why dolphins jump out of the water.  Scientists think about different reasons for this behavior.

Among them, some think that dolphins jump while traveling to save energy as going through the air consume less energy than going through the water.

Some other think that jumping is to get a better view of distant things, mainly food. So, in this way, dolphins jump to locate food or food related activity like seagulls eating or pelicans hunting.

Other explanation suggest that dolphins use jumping to communicate either with a mate or with another pod.

Some people even think that dolphins jump for cleaning, trying to get rid of parasites while jumping.

Finally some scientists think that they are only having good fun, as playing helps to keep senses at their best.

http://www.dolphins-world.com/why-do-dolphins-jump-out-of-the-water/

The idea that this double flip "saves energy" is idiotic.   The other ideas are possible.  But I think it's likely that all sufficiently intelligent life forms do stuff "just for fun".  There are plenty of good biological reasons for this, I think.

#biology___

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2016-08-21 02:02:52 (45 comments; 12 reshares; 112 +1s; )Open 

Yu Jianchun - self-taught math whiz

Henan is one of the poorer provinces of China.  But there are beautiful mountains in the county of Xinxian.   That's where Yu Jianchun grew up.  Until recently he was a package delivery worker.   He says he barely knows calculus.  But he's been working on number theory.  It took him 8 years to get anyone to pay attention to his discoveries.  But recently he was invited to give a talk at Zhejiang University!

Yu is modest:

"I'm slow-witted.  I need to spend far more time studying math problems than others. Although I am sensitive to numbers, I barely have any knowledge about calculus or geometry."

But he's made some discoveries about Carmichael numbers.  I won't define those, but they're pseudoprimes: they pass a test for being prime that Fermat invented, butthey'... more »

Yu Jianchun - self-taught math whiz

Henan is one of the poorer provinces of China.  But there are beautiful mountains in the county of Xinxian.   That's where Yu Jianchun grew up.  Until recently he was a package delivery worker.   He says he barely knows calculus.  But he's been working on number theory.  It took him 8 years to get anyone to pay attention to his discoveries.  But recently he was invited to give a talk at Zhejiang University!

Yu is modest:

"I'm slow-witted.  I need to spend far more time studying math problems than others. Although I am sensitive to numbers, I barely have any knowledge about calculus or geometry."

But he's made some discoveries about Carmichael numbers.  I won't define those, but they're pseudoprimes: they pass a test for being prime that Fermat invented, but they're not actually prime.

What did Yu Jianchun actually discover, and how impressive is it?  Unfortunately I haven't been able to find out!  Can you help? 

An article in China Topix says:

Yu Jianchun developed five formulas for the Carmichael numbers, which are pseudo-prime numbers that occur as positive integers some 255 times per 100 million. He's also developed an alternative method to verify Carmichael numbers.

"I made my discoveries through intuition," said Yu. "I would write down what I thought when inspirations struck about the Carmichael. I have hard work and make a hard living, but I insist on my studies."

Yu sent his solutions to Dr. Cai Tianxin, a math professor at Zhejiang University, along with solutions to four other problems. He later presented his solutions to the public at a graduate student seminar at the invitation of Cai. Yu's solution to complex math problem has also amazed Chinese academics.

Yu said it took over eight years of writing letters to prominent Chinese mathematicians to get any recognition for his talent.
 
"It was a very imaginative solution," said Cai.

"He has never received any systematic training in number theory nor taken advanced math classes. All he has is an instinct and an extreme sensitivity to numbers."

 In late June, China Daily told a slightly different story, with some overlap but also this:

Yu was a migrant worker in many places, and everywhere he went, he would visit the math professors at the local university, hoping to get confirmation of his formulas.

Yu said he spent eight years developing the Carmichael formulas. He has reached out to academics through emails. Cai was the first to respond.

Cai found a formula proposed by Yu to be a more efficient way of identifying Carmichael numbers and invited him to share his thinking at the university with faculty members and doctoral and postdoctoral students in a class on June 13.

Six professors and advanced students in Zhejiang University's math department listened to Yu's lecture. Some of the experts considered Yu's idea to be a "novelty", while some said "his results have a certain depth".

Cai decided to include Yu's formula with his latest work in English, and he gave Yu a book to help the logistics worker in further study.

It seems he is no Ramanujan, but still a remarkable person who could use some help.  He may finally be getting it.  CNN writes:

After local and national media reported on his findings, Yu has become a local celebrity. A company that manufactures silk products has offered him a less labor-intensive job to give him more time to study math.

Yu had never heard of the movie "Good Will Hunting," but says he's curious to see it.

The 1997 drama, which stars Matt Damon and Robin Williams, tells the fictional story of a maths genius who works as a janitor at the Massachusetts Institute of Technology.

Slightly overwhelmed by his sudden fame, Yu said he is nevertheless grateful for the new opportunities that hopefully lie ahead.

However, at age 33 and still single, he says his primary concern is to get married.

People on MathOverflow are trying to figure out, from tiny clues, what Yu has done:

http://mathoverflow.net/questions/244751/what-did-yu-jianchun-discover-about-carmichael-numbers

The China Topix article is here:

http://www.chinatopix.com/articles/95664/20160718/slow-witted-chinese-math-genius-amazes-carmichael-numbers-formulas.htm

The China Daily article is here:

http://www.chinadaily.com.cn/china/2016-06/23/content_25813818.htm

The CNN article is here:

http://edition.cnn.com/2016/07/17/asia/china-migrant-worker-good-will-hunting/index.html

To learn about Carmichael numbers, go here:

https://en.wikipedia.org/wiki/Carmichael_number

#mathematics  ___

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2016-08-18 07:02:26 (62 comments; 55 reshares; 102 +1s; )Open 

The Equation Group

We live in a world of shadowy struggles.   A team of hackers called the Equation Group has remarkable powers:

• They can reprogram your hard drive firmware.  This lets them put software on your machine that will survive even if you reformat your hard drive and reinstall your operating system.  They can create an invisible, persistent area in your hard drive, store data there, and collect it later.

• They can retrieve data from networks not connected to the internet.  They can use an infected USB stick with a hidden storage area to collect information from a computer.   When this USB stick is later plugged into a computer they've subverted that does have an internet connection, they can retrieve this information.

• Since 2001, the Equation Group has infected thousands of computers in over 30 countries, focusing ongovernment ... more »

The Equation Group

We live in a world of shadowy struggles.   A team of hackers called the Equation Group has remarkable powers:

• They can reprogram your hard drive firmware.  This lets them put software on your machine that will survive even if you reformat your hard drive and reinstall your operating system.  They can create an invisible, persistent area in your hard drive, store data there, and collect it later.

• They can retrieve data from networks not connected to the internet.  They can use an infected USB stick with a hidden storage area to collect information from a computer.   When this USB stick is later plugged into a computer they've subverted that does have an internet connection, they can retrieve this information.

• Since 2001, the Equation Group has infected thousands of computers in over 30 countries, focusing on government and diplomatic institutions, telecommunications, aerospace, energy, nuclear research, oil and gas, military, nanotechnology, Islamic activists and scholars, mass media, transportation, financial institutions and companies developing encryption technologies. 

You can see a map of computers infected by the Equation Group here:

http://cdn.arstechnica.net/wp-content/uploads/2015/02/Victims-map.png

They also seem to be connected to StuxNet, the computer worm that destroyed centrifuges used by the Iranians for uranium enrichment.

Given all this, it's a good guess that the Equation Group is connected to the NSA, the National Security Agency of the US.  I sort of hope so - because while that's scary, the alternatives scare me more. 

Now another mysterious group called Shadow Brokers has released 256 megabytes of hacking tools that may be used by the Equation Group  - and has offered to sell the rest for $500 million!   They wrote:

We follow Equation Group traffic. We find Equation Group source range. We hack Equation Group. We find many many Equation Group cyber weapons. You see pictures. We give you some Equation Group files free, you see. This is good proof no? You enjoy!!! You break many things. You find many intrusions. You write many words. But not all, we are auction the best files.

At first researchers doubted that these guys had been able to steal software from the Equation Group.  But new research at the cybersecurity firm Kaspersky Labs seems to confirm it.

Read the linked article for more!  Also try these:

On how the Equation Group was found by researchers at Kapersky Labs last year:

http://arstechnica.com/security/2015/02/how-omnipotent-hackers-tied-to-the-nsa-hid-for-14-years-and-were-found-at-last/

http://www.kaspersky.com/about/news/virus/2015/equation-group-the-crown-creator-of-cyber-espionage

On how Shadow Brokers released 256 megabytes of hacking software on their blog:

http://arstechnica.com/security/2016/08/group-claims-to-hack-nsa-tied-hackers-posts-exploits-as-proof/

Wikipedia is collecting information on the Equation Group here, so this should eventually be the best place to access information about them:

https://en.wikipedia.org/wiki/Equation_Group___

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2016-08-16 05:31:43 (16 comments; 13 reshares; 67 +1s; )Open 

Points at infinity

+Abdelaziz Nait Merzouk made this amazing movie.  Be patient!   It may take a while to load.

This is a surface living in projective space.  Projective space is like ordinary 3-dimensional space except that it has some extra points called points at infinity.   In ordinary space, parallel lines never meet.  In projective space they do!   They meet at one of these points at infinity!  

It's not as weird as you think.

Imagine two parallel train tracks.  They never meet... but they look like they meet at some point on the horizon.   That's the idea of a point at infinity.   In projective space, points on the horizon are actual points!

The geometry of projective space is important for understanding perspective, so mathematicians started working on it in the Renaissance and got really good at it bythe 1800s.  Th... more »

Points at infinity

+Abdelaziz Nait Merzouk made this amazing movie.  Be patient!   It may take a while to load.

This is a surface living in projective space.  Projective space is like ordinary 3-dimensional space except that it has some extra points called points at infinity.   In ordinary space, parallel lines never meet.  In projective space they do!   They meet at one of these points at infinity!  

It's not as weird as you think.

Imagine two parallel train tracks.  They never meet... but they look like they meet at some point on the horizon.   That's the idea of a point at infinity.   In projective space, points on the horizon are actual points!

The geometry of projective space is important for understanding perspective, so mathematicians started working on it in the Renaissance and got really good at it by the 1800s.  They still love it.  You can do lots of extra stuff that you can't do with ordinary Euclidean geometry. 

For example, a surface like this one here can extend to infinity.... and actually get there!    And there are ways to rotate a shape so that its points at infinity get moved to ordinary points that aren't at infinity!  That's what is happening in this animation.

This surface is the Endrass octic.   It has lots of points where the tips of two cones meet.    However, in the usual picture of the Endrass octic, some of these conical points are at infinity.  In this animation, they swing into view as the surface gets rotated!

So, you are now actually seeing the pictures that mathematicians have in their heads when studying projective geometry!  You can see why it's fun... and you can see why mathematicians seem absent-minded.  We're not living in your reality.  We're off in projective space!

In fact, I just lost my coffee cup.  I looked all over for it... and eventually found it, not at a point at infinity, but in the microwave!  Who put it there???

+Abdelaziz Nait Merzouk is great at making pictures of interesting surfaces.  You can see them in his collection here:

https://plus.google.com/u/0/collection/4tLusB

For more about the math of the Endrass octic, visit my blog:

http://blogs.ams.org/visualinsight/2016/08/01/endrass-octic/

This animation has a Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) copyright.  For details see https://creativecommons.org/licenses/by-sa/3.0/deed.en___

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2016-08-14 02:05:13 (46 comments; 45 reshares; 323 +1s; )Open 

Not like Earth

At the end of August, the European Southern Observatory will announce a planet orbiting Proxima Centauri - the star closest to our Sun, 4.24 light years away.   They're trying to make this planet sound like Earth... and that's cool.   But I'll tell you some ways it's not.

Mainly, Proxima Centauri is really different from our Sun! 

It's a red dwarf.   It puts out just only 0.17% as much energy as our Sun.  So any planet with liquid water must be very close to this star.

And because it's cooler than the Sun, Proxima Centauri mainly puts out infrared light - in other words, heat radiation.   Its visible luminosity is only 0.005% that of our Sun!

So if you were on a planet as warm as our Earth orbiting Proxima Centauri, it would look very dim - about 3% as bright as our Sun.

Of course,if there... more »

Not like Earth

At the end of August, the European Southern Observatory will announce a planet orbiting Proxima Centauri - the star closest to our Sun, 4.24 light years away.   They're trying to make this planet sound like Earth... and that's cool.   But I'll tell you some ways it's not.

Mainly, Proxima Centauri is really different from our Sun! 

It's a red dwarf.   It puts out just only 0.17% as much energy as our Sun.  So any planet with liquid water must be very close to this star.

And because it's cooler than the Sun, Proxima Centauri mainly puts out infrared light - in other words, heat radiation.   Its visible luminosity is only 0.005% that of our Sun!

So if you were on a planet as warm as our Earth orbiting Proxima Centauri, it would look very dim - about 3% as bright as our Sun.

Of course, if there's life on this planet, it would probably evolve to see infrared. 

But there's a more serious problem.  Proxima Centauri sometimes puts out big flares, with lots of X-rays!  That's not very nice.

Why does a wimpy little red dwarf have bigger flares than the Sun?

The Sun has a core where fusion happens, and helium produced down in the core mainly stays there.   A red dwarf doesn't have a core: it's fully convective.  In other words, heat moves through the star not by radiation, but by hot gas actually moving up to the surface. 

All this ionized gas moving around makes big magnetic fields.  The magnetic field lines get twisted up and sometimes explode out in flares!  These flares get so hot that they emit X-rays.  That's very  hot.

Our Sun has flares too, but on a smaller scale.  Even on a calm day, Proxima Centauri puts out as much X-ray energy as our Sun.  But when a big flare occurs, it can put out 10 times more.   This happens pretty often. 

So: any "Earth-like" planet orbiting this star will be a lot closer than the Earth is to our Sun, and get a lot more X-rays. 

Puzzle 1.  Use what I've told you to estimate how much closer a planet must be, to be at the same temperature as the Earth.

Puzzle 2.  Estimate how much more X-rays it will get.

On top of this, Proxima Centauri could be part of a triple star system!

The closest neighboring stars, Alpha Centauri A and B, orbit each other every 80 years. One is a bit bigger than the Sun, the other a bit smaller. They orbit in a fairly eccentric ellipse. At their closest, their distance is like the distance from Saturn to the Sun. At their farthest, it’s more like the distance from Pluto to the Sun.

Proxima Centauri is fairly far from both: a quarter of a light year away. That’s about 350 times the distance from Pluto to the Sun! We’re not even sure Proxima Centauri is gravitationally bound to the other stars. If it is, its orbital period could easily exceed 500,000 years.

On the bright side, Proxima Centauri will last a lot longer than our Sun. As it ages, it will get smaller and hotter, gradually changing from red to blue.  After about four trillion years it will grow to 2.5% of the Sun's luminosity.   When its hydrogen is exhausted, it will then become a white dwarf, without ever puffing out into a red giant like our Sun.

So, any planet orbiting this star will be a weirdly different world.  But if we ever get there, we could stay for trillions of years, long after our Sun has become a red giant, roasting life on Earth.

For rumors of ESO's announcement, see this:

http://www.universetoday.com/130276/earth-like-planet-around-proxima-centauri-discovered/

For more on Proxima Centauri, try this:

https://en.wikipedia.org/wiki/Proxima_Centauri

#astronomy  ___

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2016-08-13 06:32:47 (23 comments; 30 reshares; 155 +1s; )Open 

And even in defeat... victory!

This shows great presence of mind, and a sense of humor.

And even in defeat... victory!

This shows great presence of mind, and a sense of humor.___

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2016-08-12 05:18:30 (88 comments; 40 reshares; 258 +1s; )Open 

How big is a proton?

We thought we knew.  New measurements say we were 4% off.  That may not seem like much - but it's enough to be a serious problem!

We can measure the proton radius by bouncing electrons off it, or by carefully studying the energy levels of a hydrogen atom.  People have measured it many times, and the different measurements agree pretty well.  Here's the answer:

0.8775 ± 0.0051 femtometers   

A femtometer is 10 to the minus 15th meters, or a quadrilionth of a meter. 

But you can make a version of hydrogen with a muon replacing the electron.  The muon is the electron's big brother.  It's almost the same, but 207 times heavier.   So, muonic hydrogen is about 1/207 times as big across.  And that makes the effects of the proton radius easier to detect! 

So, in principle, weshould be abl... more »

How big is a proton?

We thought we knew.  New measurements say we were 4% off.  That may not seem like much - but it's enough to be a serious problem!

We can measure the proton radius by bouncing electrons off it, or by carefully studying the energy levels of a hydrogen atom.  People have measured it many times, and the different measurements agree pretty well.  Here's the answer:

0.8775 ± 0.0051 femtometers   

A femtometer is 10 to the minus 15th meters, or a quadrilionth of a meter. 

But you can make a version of hydrogen with a muon replacing the electron.  The muon is the electron's big brother.  It's almost the same, but 207 times heavier.   So, muonic hydrogen is about 1/207 times as big across.  And that makes the effects of the proton radius easier to detect! 

So, in principle, we should be able measure the radius of a proton more accurately using muonic hydrogen. 

So that's what they did - in Switzerland, back in 2010.  They repeated the experiment in 2013.   Here's what they got:

0.84087 ± 0.00039 femtometers
 
In theory, this is about ten times more accurate.  However, it's way off from all the earlier measurements!  7 standard deviations off.

This story is in the news again today.  The same team just used muons to measure the radius of deuterium - a proton and a neutron stuck together.  And again, they're getting a different answer than what people get using electrons.

Could some new physics be responsible?  Some serious mistake in our theory of particles?   The guy who led the new experiment, Randolph Pohl, said:

“That would, of course, be fantastic.  But the most realistic thing is that it’s not new physics.”

I like that.  A good experimentalist does not  jump to dramatic conclusions.  Pohl guesses that we're wrong about the value of the Rydberg constant, a number that goes into calculating the proton mass from the experimental data. 

However, it's worth noting that there's another puzzle about muons. Electrons and muons are like tiny magnets.  When we calculate how strong the magnetic field of an electron is, we get results that match experiment incredibly well.  But when we do the same calculation for the muon, we're off by 3.4 standard deviations.

So maybe, just maybe, there's something funny going on with muons, which hints at new physics beyond the Standard Model.  I doubt it.  But you never know.  

Check out this for more:

https://www.quantamagazine.org/20160811-new-measurement-deepens-proton-radius-puzzle/

If our estimate of the Rydberg constant were 4 standard deviations off, that would do the job.  That sounds like a lot... but if you look at the graphs here, you'll see other cases when we were way off about things!

 For even more, check out this:

• Carl E. Carlson, The proton radius puzzle, https://arxiv.org/abs/1502.05314

#physics #protonRadiusPuzzle
#spnetwork arXiv:1502.05314___

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2016-08-09 12:26:55 (16 comments; 10 reshares; 61 +1s; )Open 

WWW: the Wood Wide Web

The world wide web was not the first powerful communication network!  Long before came the wood wide web, underground in every forest.

This picture was produced by a program called Mycelium, which takes a picture and evolves it using the rules by which fungi send out tiny threads... sort of like roots... that absorb nutrients. 

A mycelium is the name for this network of threads formed by a fungus - or a bunch of fungi.   A mycelium can be huge!  In his book Mycelium Running, Paul Stamets writes:

"Is this the largest organism in the world? This 2,400-acre [970-hectare] site in eastern Oregon had a contiguous growth of mycelium before logging roads cut through it. Estimated at 1,665 football fields in size and 2,200 years old, this one fungus has killed the forest above it several times over, and in sodoing ... more »

WWW: the Wood Wide Web

The world wide web was not the first powerful communication network!  Long before came the wood wide web, underground in every forest.

This picture was produced by a program called Mycelium, which takes a picture and evolves it using the rules by which fungi send out tiny threads... sort of like roots... that absorb nutrients. 

A mycelium is the name for this network of threads formed by a fungus - or a bunch of fungi.   A mycelium can be huge!  In his book Mycelium Running, Paul Stamets writes:

"Is this the largest organism in the world? This 2,400-acre [970-hectare] site in eastern Oregon had a contiguous growth of mycelium before logging roads cut through it. Estimated at 1,665 football fields in size and 2,200 years old, this one fungus has killed the forest above it several times over, and in so doing has built deeper soil layers that allow the growth of ever-larger stands of trees."

Many plants have fungi in their roots called mycorrhizal fungi.  The mycelium of the fungus helps the plant get phosphorus and nitrogen.  In exchange, the plant feeds the fungus. 

Recently a writer for New Yorker went on a hike with an expert on this stuff named Merlin Sheldrake.    He wrote:

"Sheldrake is an expert in mycorrhizal fungi, and as such he is part of a research revolution that is changing the way we think about forests. For centuries, fungi were widely held to be harmful to plants, parasites that cause disease and dysfunction. More recently, it has become understood that certain kinds of common fungi exist in subtle symbiosis with plants, bringing about not infection but connection. These fungi send out gossamer-fine fungal tubes called hyphae, which infiltrate the soil and weave into the tips of plant roots at a cellular level. Roots and fungi combine to form what is called a mycorrhiza: itself a growing-together of the Greek words for fungus (mykós) and root (riza). In this way, individual plants are joined to one another by an underground hyphal network: a dazzlingly complex and collaborative structure that has become known as the Wood Wide Web."

What can the Wood Wide Web actually do?  We're just beginning to find out!   As I said, plants feed fungi in exchange for help getting phosphorus and nitrogen.

"The implications of the Wood Wide Web far exceed this basic exchange of goods between plant and fungi, however. The fungal network also allows plants to distribute resources—sugar, nitrogen, and phosphorus—between one another. A dying tree might divest itself of its resources to the benefit of the community, for example, or a young seedling in a heavily shaded understory might be supported with extra resources by its stronger neighbors. Even more remarkably, the network also allows plants to send one another warnings. A plant under attack from aphids can indicate to a nearby plant that it should raise its defensive response before the aphids reach it. It has been known for some time that plants communicate above ground in comparable ways, by means of airborne hormones. But such warnings are more precise in terms of source and recipient when sent by means of the myco-net."

Read the whole article here:

http://www.newyorker.com/tech/elements/the-secrets-of-the-wood-wide-web

The program Mycelium was created by Ryan Alexander, who writes:

"Hyphae grow into the lighter areas of the image while avoiding their own trails. Branching and growth speed are also functions of the available food (brightness) in the image. Type can be added by splitting the trails up into phrase-sized chunks of different colors. Each color is then stroked with text in Adobe Illustrator."

That's right: the little hairs or 'hyphae' are actually strings of text if you look at them closely!  You can see that here:

https://www.flickr.com/photos/onecm/sets/72157600033861485/

Merlin Sheldrake is the son of Rupert Sheldrake, and I hope he is a better scientist - otherwise I can't really trust his work.  ___

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2016-08-08 04:51:46 (0 comments; 89 reshares; 197 +1s; )Open 

What's wrong with Trump?

More and more people are wondering.  Here's an insightful analysis from a psychiatric social worker.  Please reshare.  It's not light reading, but we need to understand what we're dealing with here.

--------------------

The Billionaire's Baffling Behavior Explained

Recently, Mr. Trump's words and actions in various situations have become headline news. Suddenly, many people are alarmed and are questioning temperament, his emotional stability. Dementia? Campaign tactics?

No, it's not an illness that can be treated so he can return to his usual state of health. It's not like when a car's brakes don't work and the mechanic fixes them. It's more like the car came off the assembly line without them.

It's a structural problem.

We're witnessingte... more »

What's wrong with Trump?

More and more people are wondering.  Here's an insightful analysis from a psychiatric social worker.  Please reshare.  It's not light reading, but we need to understand what we're dealing with here.

--------------------

The Billionaire's Baffling Behavior Explained

Recently, Mr. Trump's words and actions in various situations have become headline news. Suddenly, many people are alarmed and are questioning temperament, his emotional stability. Dementia? Campaign tactics?

No, it's not an illness that can be treated so he can return to his usual state of health. It's not like when a car's brakes don't work and the mechanic fixes them. It's more like the car came off the assembly line without them.

It's a structural problem.

We're witnessing textbook Cluster B Personality Disorders come to life, revealing his intra-psychic structure, particular lens on reality and associated defense mechanisms.

Clinically, it's fascinating.

Politically, it's frightening.

This is who Trump is, how he sees the world and others in it and how he will continue to function. At 68, without acknowledging any internal difficulties and/or any desire to change them, this is how he will continue forever. Introspection and self-analysis are rarely typical of personality disordered individuals. These behaviors are no surprise; in fact they're utterly predictable.

Before I continue though, let me head off some opposition.

YES, everyone has some level of narcissism; a certain amount is actually healthy. It allows one to advocate for oneself, not be taken advantage of and, based on a reasonable assessment of one's strengths, take risks to apply those abilities to start a new business, try out for a minor league MLB slot or take a step up the occupational ladder, for instance. Politicians, ALL of them, have more than the average person, required to withstand the vagaries of our current election process.

But, "healthy narcissism " differs from Trump's version. His is "grandiosity ", a rigidly held, yet fragile exaggerated sense of self-importance where one is special, unique, superior to others, often without the associated level of grand accomplishment.

"Healthy narcissism " is reasonable self-confidence when an accomplished person says "I have some good ideas that could help solve this problem."

In contrast, you see Trump's "grandiosity " in the statement "I alone can fix it."

How grandiose to believe one can run for the highest political office in the land without a day of previous experience or even a modicum of interest in geo-political issues. Trump's grandiosity led him to waltz into the casino & "education" businesses with no prior experience and look at the results. Anyway, back to psychology:

A personality disorder is essentially a developmental arrest, a mosaic of maladaptive personality traits which create a distorted lens through which one views self and others and influences one's interactions. We all have these aspects to our personalities, but with PD's [personality disorders], it's a matter of greater frequency and degree. Certain psychic defense mechanisms are correlated with specific phases of development in more or less chronological order. They basically function to help the person moderate internal needs and desires to the demands of reality. When those are at odds, defenses are meant to help protect the core "self" from the resultant anxiety. When lower level, more primitive defense mechanisms are the characteristic mode of behavior one relies on, it moves into the personality disorder category.

Underlying all PDs, no matter the external "flavor", is the failure to have reached the psychic developmental level where disparate, opposing aspects of self and other are able to be mentally integrated into a cohesive whole. This underlies one of the most important associated defense mechanisms, that of "splitting ", which becomes the filter through which self, others & events are perceived.

In splitting, discrepant aspects of an image or object cannot be held in consciousness at the same time. Everything's either "all bad" or "all good" but never both together at the same time. Look at Trump's constant usage of these superlatives when describing others. No integrated "sometimes he's ok, sometimes not." If you listen carefully, you won't hear this type of response unless the wording has been previously crafted by another in a speech or statement. No supportive factual content, just one sided emotional reactivity. Never an explanation why a person is "horrible, the worst" or "very good guy, great person", just the judgemental superlatives.

This non-integration usually goes hand in hand with "projection" and "projective identification " (it's complicated.) It's much simpler to categorize others that way and initially, it wards off anxiety associated with cognitive dissonance,but it prevents the assimilation of all information. Without all the discrepant data about self or other though, invariably the "unexpected " will appear, for which one is unprepared, then: anxiety! This leads to that chronic hyper-vigilance often seen with PDs. The fear provoked by this amorphous unknown is then "projected" onto an object, which becomes a concrete target.

Negative aspects of the self cannot be integrated into a positive self-image (i.e. criticism like "ignorant " or "arrogant ") so are often projected onto another and then denigrated. The most recent example of projective identification is that for the past week, people have been questioning Trump's mental stability. Yesterday, he called Hillary Clinton "unstable" and "unhinged ", the same words recently used to describe him. No example to support the claim... I imagine he was vaguely instructed to criticize Hillary without specific guidance. Although there is more than enough ammunition, his obsession with "self" and "image" is apparent in his choice of off the mark insults.

Back to splitting:

Because self and others aren't seen in their full conflicting, complex reality, PDs hold mental representations akin to superficial caricatures. They tend to disregard the thoughts and feelings of others and fail to consider the consequences of their own actions on others because their mental representations of others just aren't imbued with these qualities. The self focus of NPDs is so constant and obsessive, there's no room or concern for consideration of others. In other words, others just don't matter. This behavior is what some happily, but mistakenly announce is his not caring about being "politically correct". Actually, it's really a symptom of his disturbance.

Splitting is also the explanation behind what are his constant examples of contradictory statements about a multitude of subjects over time. It differs qualitatively from "lying" per se, although I'm sure he does that too.

Lying is an intentional deceptive act often associated with some secondary gain, such as avoidance of consequences. The person is fully aware that what they are saying differs from the actual facts. In splitting, the contradictory concepts cannot mentally coexist at the same time. Trump believes what he says when he it. Because his mental state may differ today from two weeks ago, his view point on the same subject will vacillate too. Contradictions for most cause conflict but his psychic makeup disavows discrepancy before it gets to that point. But remember, this is an unconscious process... it just doesn't go in, it remains foreign, it's not "owned" and explained (in spite of video). Contradictory statements will, at best, be minimally acknowledged in terms that they've occurred, but disregarded as unimportant, shrugged off because they no longer connect on an intra-psychic level. He's almost surprised that these discrepancies are attributed to him all. Thus, they cause no anxiety.

I truly pity his team of campaign strategists having to negotiate this mine field. PDs are notorious for leaving chaos and distress in their wake while they go happily along without any care in the world.

PD's are a product of both nature and nurture. As one goes through maturational phases, the demands of reality increase and through experiencing the invariable failures, frustrations and disappointments, more evolved mechanisms like "repression " or "rationalization " ideally develop and replace the more inadequate primitive ones. For most people, but not all.

We are seeing Mr. Trump struggle to use his inadequate set of rigid, primitive defense mechanisms to manage real world demands, apparently for the FIRST TIME.

The very rich really ARE different.

If you recall, while Donald was growing up, his father Fred was one of the richest men in the world.

The very wealthy have the resources to create a universe which, while protective, also serves to reinforce any dysfunction. Critics or nay-sayers are removed from their orbit, replaced with loyalists who rationalize or ignore the dysfunction. Often in the presence of celebrity or great wealth, otherwise intelligent reasonable people become fawning syncophants.

Trump never had to follow any rules; they didn't apply to him. Punch a teacher? Simple fix: change schools. Potential draft material? Find a doctor to submit a medical deferment (bone spurs in the foot prevent military service but don't prevent playing baseball?). He went into the family business so never had a critical boss. Keep digging and you find his claims of great ability exaggerated or actually non-existent; doesn't matter that the narrative is false as long as it reinforces the self-image.

Anyway, back to the present:

The goal with an NPD [narcissistic personality disorder] person is to protect & reinforce the simultaneously fragile & grandiose core. It's almost as if without the constant attention, it's feared that the self may disintegrate. Because the self-image is so tenuous, they need inordinate amounts of external approval & rely on a defense called "mirroring"... You're great because you think I'm great, etc.... He gets this at his rallies with core supporters. This inordinate need for excessive approval may also underlie his reluctance to disavow questionable supporters, like David Duke.

With criticism, an ego this brittle experiences it as an impending attack which threatens the very existence of the core self and triggers what's called "narcissistic rage" followed often by a reflexive aggressive response.

He calls it "counter-punching" but it's truly acting out in response to the rage.

This has always been his response.

Within the security of Trump World, no one criticized this behavior before, ever. In one video of him, he seems truly baffled that anyone would view him differently than he views himself. He says "Even if you don't like me, you have to vote for me. You have to."

He's had no prior experience with this type of ego threat from long-term microscopic scrutiny. Previously, it's been intermittent or his public presentation has been structured to coincide with his inflated self-image, such as his reality show.

Someone with such a fragile self-image will take the bait constantly , whether it's from a Gold Star American family or another world leader.

He cannot help himself. It's ego life or death.

Splitting also explains his lack of coherent political philosophy; issues are presented piecemeal, disconnected from other. If some of the data is conflictual it can't exist in the consciousness, so no possible way to create a grand plan based on a cohesive frame of reference. Just not possible. It also explains the apparent self-defeating behavior toward prominent Republicans. Each slight is responded to in isolation without any comprehension how one spat, like with McCain or Ryan, affect his relationship to the whole group.

No, he isn't "calculating" and "crazy like a fox", although he may be decompensating under stress.

He may not become truly psychotic in the classic Axis I sense of the definition; however, there seems to be more paranoia emerging as he hasn't developed psychic resources capable of effectively warding off the disequilibrium brought on by the onslaught of scrutiny and criticism. Recently he's said the current administration has allowed "thousands upon thousands " of terrorists into the country, fears the election will be "rigged" without ANY factual basis for support.

This kind of thinking will probably remit when there's less pressure, but it will resurface anytime stress intensifies.

It is no surprise that his children function better than he; for much of their lives they were raised in separate home environments by his ex-wives. Both divorce settlements were accompanied by "non-disclosure agreements", aka "gag orders".

Trump's "missteps", "misstatements" and "walk backs" which characterize his campaign are not due to his "rookie" politician status. They are a true reflection of how he functions.

And the "he tells it like it is" assertion? That actually used to be a euphemism meaning "truthful ". He tells you what he's thinking at the moment but it doesn't mean it has any connection to reality or fact.

Please stop "Waiting for him to change". He cannot. (There's no Easter Bunny either, by the way.)

Just admit you were star-struck, misled by his grandiosity or made incorrect assumptions about his business acumen based on 24k gold bathroom fixtures and call it a day.

--------------------

This is from here:

https://www.yabberz.com/post/the-billionaires-baffling-behavior-explained/86689585/

I thank +Boris Borcic for pointing it out.___

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2016-08-05 15:24:03 (31 comments; 11 reshares; 88 +1s; )Open 

The quest for beauty

This is a nice interview of Miranda Cheng, an assistant professor at the University of Amsterdam working on the math of string theory.   She's on a quest to understand the connection between strings and some mysterious functions in Ramanujan's lost notebook.

It's sort of spooky how much of Ramanujan's work makes more sense with the help of string theory.   But perhaps it shouldn't be surprising.  String theory hasn't really done anything to predict the results of experiments - it's mainly attractive because of its mathematical beauty.  Ramanujan, too, was motivated by the quest for beauty.   He got there sooner... but he only saw the tip of the vast iceberg we're exploring now.

What's "mathematical beauty"?    Here's what Cheng says:

It’s kind of hard to say why it isbeautiful. I... more »

The quest for beauty

This is a nice interview of Miranda Cheng, an assistant professor at the University of Amsterdam working on the math of string theory.   She's on a quest to understand the connection between strings and some mysterious functions in Ramanujan's lost notebook.

It's sort of spooky how much of Ramanujan's work makes more sense with the help of string theory.   But perhaps it shouldn't be surprising.  String theory hasn't really done anything to predict the results of experiments - it's mainly attractive because of its mathematical beauty.  Ramanujan, too, was motivated by the quest for beauty.   He got there sooner... but he only saw the tip of the vast iceberg we're exploring now.

What's "mathematical beauty"?    Here's what Cheng says:

It’s kind of hard to say why it is beautiful. It’s beautiful not the same way as a song is beautiful or a picture is beautiful.  Typically a song is beautiful because it triggers certain emotions. It resonates with part of your life. Mathematical beauty is not that. It’s something much more structured. It gives you a feeling of something much more permanent, and independent of you. It makes me feel small, and I like that.

The interviewer asked if she always had a knack for math, and she replied:

As a child in Taiwan I was more into literature — that was my big thing. And then I got into music when I was 12 or so — pop music, rock, punk. I was always very good at math and physics, but I wasn’t really interested in it. And I always found school insufferable and was always trying to find a way around it. I tried to make a deal with the teacher that I wouldn’t need to go into the class. Or I had months of sick leave while I wasn’t sick at all. Or I skipped a year here and there. I just don’t know how to deal with authority, I guess.

And the material was probably too easy. I skipped two years, but that didn’t help. So then they moved me to a special class and that made it even worse, because everybody was very competitive, and I just couldn’t deal with the competition at all. Eventually I was super depressed, and I decided either I would kill myself or not go to school. So I stopped going to school when I was 16, and I also left home because I was convinced that my parents would ask me to go back to school and I really didn’t want to do that. So I started working in a record shop, and by that time I also played in a band, and I loved it.

Long story short, I got a little bit discouraged or bored. I wanted to do something else aside from music. So I tried to go back to university, but then I had the problem that I hadn’t graduated from high school. But before I quit school I was in a special class for kids who are really good in science. I could get in the university with this. So I thought, OK, great, I’ll just get into university first by majoring in physics or math, and then I can switch to literature. So I enrolled in the physics department, having a very on- and off-again relationship to it, going to class every now and then, and then trying to study literature, while still playing in the band. Then I realized I’m not good enough in literature. And also there was a very good teacher teaching quantum mechanics. Just once I went to his class and thought, that’s actually pretty cool. I started paying a bit more attention to my studies of math and physics, and I started to find peace in it. That’s what started to attract me about math and physics, because my other life in the band playing music was more chaotic somehow. It sucks a lot of emotions out of you. You’re always working with people, and the music is too much about life, about emotions — you have to give a lot of yourself to it. Math and physics seems to have this peaceful quiet beauty. This space of serenity.

How true, how true!   Read the whole interview!

For more on what Cheng is up to, try this Wikipedia article:

https://en.wikipedia.org/wiki/Umbral_moonshine

I wish I had time to really dig into this stuff!  It combines lots of things I like: string theory, K3 surfaces, the 24 even unimodular lattices in 24 dimensions, the Mathieu group M24... hmm, did you notice how the number 24 keeps coming up here?  That's part of the charm and mystery of this part of math.

Thanks to +David Roberts for pointing out this interview. 

#physics  ___

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2016-08-04 05:25:21 (16 comments; 11 reshares; 65 +1s; )Open 

Endrass octic

This surface looks cute - but it's also the best known solution to a hard math problem.  It's called the Endrass octic

Why 'Endrass'?  Because was discovered in 1995 by Stephan Endrass while he was writing his Ph.D. thesis. 

Why 'octic'?  Because it's described by a polynomial equation of degree 8.

You'll notice it has lots of points where the tips of two cones meet.   It has 168 of them, though not all are visible here.  And this is, so far, the largest number of such points that people have gotten for an octic.

It may not be the best possible.   But it's the best so far.  In 1984, a guy named Miyaoka showed that you can't get get more than 174 of these conical points in an octic.  So, there's a gap between what we know is possible and what might be possible.   (If you're... more »

Endrass octic

This surface looks cute - but it's also the best known solution to a hard math problem.  It's called the Endrass octic

Why 'Endrass'?  Because was discovered in 1995 by Stephan Endrass while he was writing his Ph.D. thesis. 

Why 'octic'?  Because it's described by a polynomial equation of degree 8.

You'll notice it has lots of points where the tips of two cones meet.   It has 168 of them, though not all are visible here.  And this is, so far, the largest number of such points that people have gotten for an octic.

It may not be the best possible.   But it's the best so far.  In 1984, a guy named Miyaoka showed that you can't get get more than 174 of these conical points in an octic.  So, there's a gap between what we know is possible and what might be possible.    (If you're into algebraic geometry you might like Miyaoka's paper - he used some pretty fancy techniques.)

Endrass actually found two octics with 168 conical points.  You can see pictures of both, drawn by +Abdelaziz Nait Merzouk, over at my blog:

http://blogs.ams.org/visualinsight/2016/08/01/endrass-octic/

They're very beautiful.  You can also see the equations of these surfaces.  They're not very beautiful, at least not to me.  Endrass found them with the help of a computer algebra system. 

The animation I'm showing you here comes from a German math website:

• IMAGINARY: open mathematics, https://imaginary.org/tr/node/626

Request: Can someone draw beautiful pictures of the Cayley cubic, the Kummer quartic and the Togliatti quintic?  Those are the surfaces described by equations of degree 3, 4, and 5 with the maximum number of conical points.  They're pretty nice:

https://en.wikipedia.org/wiki/Cayley%27s_nodal_cubic_surface
https://en.wikipedia.org/wiki/Kummer_surface
https://en.wikipedia.org/wiki/Togliatti_surface

Wikicommons has decent pictures of the first and last ones. I'd like to discuss these surfaces on my blog.  It would be nice to have truly spectacular pictures.

#geometry  ___

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2016-08-03 05:12:57 (29 comments; 69 reshares; 146 +1s; )Open 

Primes with no sevens

This is a prime number whose decimal digits are all ones.  It has 317 ones.  It's not the world record.  The number with 1031 ones is also known to be prime! 

Even larger guys like this are suspected  to be prime.  Are there infinitely many?   Mathematicians believe so, but they can't prove it.

Why do they believe it?   The main reason is that they have an estimate of the "probability" that a number with some number of digits is prime. We can use this to guess the answer to this puzzle.

Of course the whole idea of "probability" is a bit weird here.  A number is either prime or not: the math gods do not flip coins to decide which numbers are prime! 

Nonetheless, treating primes as if  they were random turns out to be useful.   Mathematicians have made many guesses using this idea, andthen proved ... more »

Primes with no sevens

This is a prime number whose decimal digits are all ones.  It has 317 ones.  It's not the world record.  The number with 1031 ones is also known to be prime! 

Even larger guys like this are suspected  to be prime.  Are there infinitely many?   Mathematicians believe so, but they can't prove it.

Why do they believe it?   The main reason is that they have an estimate of the "probability" that a number with some number of digits is prime. We can use this to guess the answer to this puzzle.

Of course the whole idea of "probability" is a bit weird here.  A number is either prime or not: the math gods do not flip coins to decide which numbers are prime! 

Nonetheless, treating primes as if  they were random turns out to be useful.   Mathematicians have made many guesses using this idea, and then proved these guesses are right, using a lot of extra work.

Of course it's subtle.  If I wrote down a number with 317 twos in its decimal expansion, you'd instantly know it's not prime - because it would be even.

In the European Congress of Mathematics, a number theorist named James Maynard just announced something cool.  There are infinitely many prime numbers with no sevens in their decimal expansion!

And his proof works equally well for any other number: there infinitely many primes without 0 as a digit, or 1, or 2, or 3, or 4, or 5, and so on.

This is big news, but not because mathematicians really care about primes with no sevens in them.  It's because proving something like this requires a deep and delicate understanding of "the music of primes" - the way prime numbers are connected to wave patterns.  For more on that, here's something easy to read:

https://plus.maths.org/content/missing-7s

Thanks to +Luis Guzman for pointing out this article, and thanks to +David Roberts for finding James Maynard's paper on this subject, which is here:

• James Maynard, Primes with restricted digits, http://arxiv.org/abs/1604.01041.

He shows that if your base b is sufficiently large, you can find infinitely many primes that are lacking a chosen set of digits, where this set can contain up to b^(23/80) of the digits.  Unfortunately I don't see  how large b must be - he may not have worked this out.  If b = 10 counts as sufficiently large, then since 10^(23/80) is about 1.94, this result would let you avoid any one digit in base 10, but not two.  In any event, he does prove, separately, that you can find infinitely many primes that avoid any one digit in base 10.

  It uses cool techniques, like "decorrelating Diophantine conditions which dictate when the Fourier transform of the primes is large from digital conditions which dictate when the Fourier transform of numbers with restricted digits is large".  It also uses ideas from Markov process theory - that is, the theory of random processes - as well as hard-core number theory concepts.

#bigness   #spnetwork arXiv:1604.01041 #numberTheory #primes  ___

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2016-08-01 02:27:09 (8 comments; 12 reshares; 107 +1s; )Open 

Single-minded determination meets gentle courtesy

Single-minded determination meets gentle courtesy___

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2016-07-31 02:44:02 (36 comments; 19 reshares; 103 +1s; )Open 

The search for dark matter

In South Dakota, in a town named Lead, there was a gold mine.  Now it's abandoned.   But at the bottom of this mine, more than a mile underground, there sits a one-meter-tall, 12-sided container.  It contains 370 kilograms of a noble gas chilled to liquid form.  Liquid xenon!  

It's called the Large Underground Xenon experiment, or LUX.  It's been looking for particles that could explain dark matter.   If such a particle interacts with a xenon atom, LUX can detect it. 

Of course, we also need to distinguish these particles from other things. Xenon, a gas at room temperatures, chilled to liquid form, is a great choice here.  For one thing, it's self-shielding!  Xenon is so dense that most gamma rays and neutrons don't get through more than a few centimeters of the stuff.  But it's perfectlytransparent t... more »

The search for dark matter

In South Dakota, in a town named Lead, there was a gold mine.  Now it's abandoned.   But at the bottom of this mine, more than a mile underground, there sits a one-meter-tall, 12-sided container.  It contains 370 kilograms of a noble gas chilled to liquid form.  Liquid xenon!  

It's called the Large Underground Xenon experiment, or LUX.  It's been looking for particles that could explain dark matter.   If such a particle interacts with a xenon atom, LUX can detect it. 

Of course, we also need to distinguish these particles from other things. Xenon, a gas at room temperatures, chilled to liquid form, is a great choice here.  For one thing, it's self-shielding!  Xenon is so dense that most gamma rays and neutrons don't get through more than a few centimeters of the stuff.  But it's perfectly transparent to ordinary light... so if a dark matter particle hits an atom of xenon in the middle of the tank, LUX will see a flash of light.  It can also detect electrons that shoot out from the collision.

Four other experiments had reported hints of dark matter particles about 5 times heavier than a proton.  But LUX is much more sensitive!

The LUX team, with over a hundred scientists, has been looking for dark matter since 2014.  Ten days ago they announced their results: no dark matter particles seen.

This "non-discovery" is actually an important discovery.  The most popular theory of dark matter - that it consists of weakly interacting massive particles - has taken a serious hit. 

We now know that if these hypothetical particles, affectionately called WIMPs, are responsible for most of the dark matter and have a mass between 1/5 and 1000 times the mass of a proton, they must be very, very unwilling to interact with ordinary matter. 

There's no rule saying particles have to interact with ordinary matter.  So, we can't rule out such WIMPs, but they're looking less plausible.  People are getting more interested in other theories:

1) theories with very light WIMPs, such as axions or new kinds of neutrinos

2) theories with very heavy WIMPs, jokingly called WIMPzillas

3) theories where dark matter consists of large objects such as black holes.

In case you're wondering whether dark matter really exists: there's so much evidence for this that very few scientists question it anymore.

Theory 3) is getting a lot of attention, because the gravitational wave detector called LIGO is now able to detect black hole collisions!  It's seen two collisions so far, and the first one involved black holes that seem quite strange, not like the ones we know.  They might be primordial black holes, left over from the early Universe.   Perhaps dark matter consists of primordial black holes!

More on that later.  For now, try these.  The new announcement from the LUX team is here:

http://luxdarkmatter.org/LUX_dark_matter/Talks_files/LUX_NewDarkMatterSearchResult_332LiveDays_IDM2016_160721.pdf

For how the LUX detector works, read this nice article:

http://www.quantumdiaries.org/2014/04/17/searching-for-dark-matter-with-the-large-underground-xenon-experiment/

For a nice intro to the LUX results by Ethan Siegel, on a website that requires you to look at ads, try this:

http://www.forbes.com/sites/startswithabang/2016/07/21/dark-matter-may-be-completely-invisible-concludes-worlds-most-sensitive-search/

For primordial black holes as dark matter, try this:

http://resonaances.blogspot.com/2016/06/black-hole-dark-matter.html

The picture is from this article:

http://www.symmetrymagazine.org/image/april-2012-dark-matter-underground

#physics  ___

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2016-07-30 05:17:01 (33 comments; 9 reshares; 72 +1s; )Open 

Death of the diphoton bump

In June 2015, after a two-year upgrade, the Large Hadron Collider turned on again.  In its first run it had discovered the Higgs boson, a particle 133 times heavier than the proton — and the main missing piece of the Standard Model.   When the collider restarted, with a lot more energy, everyone was hoping to see something new.

In December 2015, two separate detectors saw something: pairs of photons, seemingly emitted by the decay of a brand new particle 6 times heavier than the Higgs boson.  

But was it for real?   Maybe it was just a random fluctuation — noise, rather than a true signal. 

It seemed unlikely to be just chance.  Combining the data from both detectors, the chance of coincidentally seeing a bump this big at this location in the photon spectrum was one in 100 thousand. 

But in particle physicsthat's n... more »

Death of the diphoton bump

In June 2015, after a two-year upgrade, the Large Hadron Collider turned on again.  In its first run it had discovered the Higgs boson, a particle 133 times heavier than the proton — and the main missing piece of the Standard Model.   When the collider restarted, with a lot more energy, everyone was hoping to see something new.

In December 2015, two separate detectors saw something: pairs of photons, seemingly emitted by the decay of a brand new particle 6 times heavier than the Higgs boson.  

But was it for real?   Maybe it was just a random fluctuation — noise, rather than a true signal. 

It seemed unlikely to be just chance.  Combining the data from both detectors, the chance of coincidentally seeing a bump this big at this location in the photon spectrum was one in 100 thousand. 

But in particle physics that's not good enough.  Physicists are looking for lots of different things in these big experiments, so rare coincidences do happen.  To feel safe, they want to push the chance down to one in 3 million.  That's called a 5 sigma event.

So they looked harder. 

Meanwhile, theoretical physicists wrote 500 papers trying to explain this so-called diphoton bump.  It turned out to be easy to make up theories that have a particle of the right sort.  Not so easy, though, to make a convincingly elegant theory.

New data have come in.  The bump is gone.

Theorists are bummed.  A particle physicist named Adam Falkowski wrote:

The loss of the 750 GeV diphoton resonance is a big blow to the particle physics community. We are currently going through the 5 stages of grief, everyone at their own pace, as can be seen e.g. in this comments section. Nevertheless, it may already be a good moment to revisit the story one last time, so as  to understand what went wrong.

In the recent years, physics beyond the Standard Model has seen 2 other flops of comparable impact: the faster-than-light neutrinos in OPERA, and the cosmic microwave background tensor fluctuations in BICEP.  Much as the diphoton signal, both of the above triggered a binge of theoretical explanations, followed by a massive hangover. There was one big difference, however: the OPERA and BICEP signals were due to embarrassing errors on the experimentalists' side. This doesn't seem to be the case for the diphoton bump at the Large Hadron Collider. Some may wonder whether the Standard Model background may have been slightly underestimated,  or whether one experiment may have been biased by the result of the other... But, most likely, the 750 GeV bump was just due to a random fluctuation of the background at this particular energy. Regrettably, the resulting mess cannot be blamed on experimentalists, who were in fact downplaying the anomaly in their official communications. This time it's the theorists who  have some explaining to do.

For more, see Adam Falkowski's blog.  He goes by the name of "Jester":

http://resonaances.blogspot.sg/2016/07/after-hangover.html

By now we have to admit it's quite possible that the Large Hadron Collider will not see any new physics not predicted by the Standard Model.   Unfortunately, this triumph of the Standard Model would leave a lot of big questions unanswered... for now.

The video explains the diphoton bump in simple terms.  It was made back in the early optimistic days.

#physics  ___

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2016-07-29 04:16:41 (0 comments; 28 reshares; 107 +1s; )Open 

Melania Trump has disappeared

Her website was deleted on Wednesday.   Check it out:

http://www.melaniatrump.com

But it's not so easy to make things disappear on the internet!  You can still see what it looked like ten days ago:

https://web.archive.org/web/20160719142534/http://www.melaniatrump.com/

Why was it deleted?   Melania Trump didn't really get a degree of architecture.  Her website said:

After obtaining a degree in design and architecture at University in Slovenia, Melania was jetting between photo shoots in Paris and Milan, finally settling in New York in 1996.

But in fact she dropped out before getting a degree.   She attended the University of Ljubljana’s architecture school... but quit after her freshman year! 

I don't think this lie - or her plagiarized speech - is a bigdeal com... more »

Melania Trump has disappeared

Her website was deleted on Wednesday.   Check it out:

http://www.melaniatrump.com

But it's not so easy to make things disappear on the internet!  You can still see what it looked like ten days ago:

https://web.archive.org/web/20160719142534/http://www.melaniatrump.com/

Why was it deleted?   Melania Trump didn't really get a degree of architecture.  Her website said:

After obtaining a degree in design and architecture at University in Slovenia, Melania was jetting between photo shoots in Paris and Milan, finally settling in New York in 1996.

But in fact she dropped out before getting a degree.   She attended the University of Ljubljana’s architecture school... but quit after her freshman year! 

I don't think this lie - or her plagiarized speech - is a big deal compared to Trump's other lies.   It's just another small example of the dishonesty and utter lack of respect for reality  displayed by Donald Trump and his minions. 

Do we really want a president who repeatedly pretended to be someone else, then admitted in court that he did this... and now says he never did it?

The voice is instantly familiar; the tone, confident, even cocky; the cadence, distinctly Trumpian. The man on the phone vigorously defending Donald Trump says he’s a media spokesman named John Miller, but then he says, “I’m sort of new here,” and “I’m somebody that he knows and I think somebody that he trusts and likes” and even “I’m going to do this a little, part time, and then, yeah, go on with my life.”

A recording obtained by The Washington Post captures what New York reporters and editors who covered Trump’s early career experienced in the 1970s, ’80s and ’90s: calls from Trump’s Manhattan office that resulted in conversations with “John Miller” or “John Barron” — public-relations men who sound precisely like Trump himself — who indeed are Trump, masquerading as an unusually helpful and boastful advocate for himself, according to the journalists and several of Trump’s top aides.

In 1990, Trump admitted in a court case that “I believe on occasion I used that name", meaning John Miller.  But this year he lied again:

In a phone call to NBC’s “Today” program Friday morning after this article appeared online, Trump denied that he was John Miller.  “No, I don’t think it — I don’t know anything about it. You’re telling me about it for the first time and it doesn’t sound like my voice at all,” he said. “I have many, many people that are trying to imitate my voice and then you can imagine that, and this sounds like one of the scams, one of the many scams — doesn’t sound like me.” Later, he was more definitive: “It was not me on the phone. And it doesn’t sound like me on the phone, I will tell you that, and it was not me on the phone. And when was this? Twenty-five years ago?”

Or maybe the person on the phone to NBC wasn't Trump!  Maybe it was John Miller!

For more details about Trump pretending to be his own spokesman:

https://www.washingtonpost.com/politics/donald-trump-alter-ego-barron/2016/05/12/02ac99ec-16fe-11e6-aa55-670cabef46e0_story.html

For more details about Melania's amazing disappearing website:

http://www.huffingtonpost.com/entry/melania-trump-biography-deleted_us_57990c1ae4b02d5d5ed3fed9

http://www.huffingtonpost.com/entry/melania-trump-college-claims_us_578dd95ce4b0c53d5cfac0dc___

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2016-07-27 04:02:07 (59 comments; 12 reshares; 96 +1s; )Open 

Satanic crystal found in ancient meteorite

Just kidding!  There's nothing devilish about the pentagram here.  It's what scientists saw when they shot X-rays through a tiny piece of a meteorite found in the far northeast of Russia. 

No ordinary crystal can produce this pattern  - it takes a quasicrystal, where the atoms are packed in a way that never quite repeats.  Scientists have made lots of quasicrystals in the lab, but only two have been found in nature, both in meteorites!

This is the second one.  It contains a mineral called icosahedrite, made of aluminum, copper and iron.  It's only stable at high temperatures and pressures, so it must have formed in a collision.  It's been slowly decaying ever since, but very slowly.  It could be billions of years old.

To see how this mineral could have formed, scientistssimulate... more »

Satanic crystal found in ancient meteorite

Just kidding!  There's nothing devilish about the pentagram here.  It's what scientists saw when they shot X-rays through a tiny piece of a meteorite found in the far northeast of Russia. 

No ordinary crystal can produce this pattern  - it takes a quasicrystal, where the atoms are packed in a way that never quite repeats.  Scientists have made lots of quasicrystals in the lab, but only two have been found in nature, both in meteorites!

This is the second one.  It contains a mineral called icosahedrite, made of aluminum, copper and iron.  It's only stable at high temperatures and pressures, so it must have formed in a collision.  It's been slowly decaying ever since, but very slowly.  It could be billions of years old.

To see how this mineral could have formed, scientists simulated the collision between two asteroids in their lab.  They took thin slices of minerals found in the Khatyrka meteorite and sandwiched them together in a gadget that looks like a a steel hockey puck.  They attached it to the muzzle of a four-meter-long gun and blasted it with a projectile moving nearly one kilometer per second! 

Yup.  Icosahedrite.

For details and more pictures, see:

• Paul D. Asimow, Chaney Lin, Luca Bindi, Chi Ma, Oliver Tschauner, Lincoln S. Hollister and Paul J. Steinhardt, Shock synthesis of quasicrystals with implications for their origin in asteroid collisions, Proceedings of the National Academy of Sciences 113 (2016), 7077-7081.  Freely available at http://authors.library.caltech.edu/67876/

Puzzle: how did pentagrams get associated with Satan in the first place?

#astronomy #geometry
#spnetwork DOI:10.1073/pnas.1600321113___

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2016-07-26 06:47:27 (0 comments; 9 reshares; 72 +1s; )Open 

What Sanders thinks about Clinton and Trump

I've never lived through an election where the choice is so stark - where the consequences of our vote will be so huge.  Bernie Sanders laid it out clearly at the Democratic National Convention yesterday:

This election is about which candidate understands the real problems facing this country and has offered real solutions – not just bombast, fear-mongering, name-calling and divisiveness.

We need leadership in this country which will improve the lives of working families, the children, the elderly, the sick and the poor. We need leadership which brings our people together and makes us stronger – not leadership which insults Latinos, Muslims, women, African-Americans and veterans – and divides us up.

By these measures, any objective observer will conclude that – based on her ideas andher lead... more »

What Sanders thinks about Clinton and Trump

I've never lived through an election where the choice is so stark - where the consequences of our vote will be so huge.  Bernie Sanders laid it out clearly at the Democratic National Convention yesterday:

This election is about which candidate understands the real problems facing this country and has offered real solutions – not just bombast, fear-mongering, name-calling and divisiveness.

We need leadership in this country which will improve the lives of working families, the children, the elderly, the sick and the poor. We need leadership which brings our people together and makes us stronger – not leadership which insults Latinos, Muslims, women, African-Americans and veterans – and divides us up.

By these measures, any objective observer will conclude that – based on her ideas and her leadership – Hillary Clinton must become the next president of the United States. The choice is not even close.

This election is about a single mom I saw in Nevada who, with tears in her eyes, told me that she was scared to death about the future because she and her young daughter were not making it on the $10.45 an hour she was earning. This election is about that woman and the millions of other workers in this country who are struggling to survive on totally inadequate wages.

Hillary Clinton understands that if someone in America works 40 hours a week, that person should not be living in poverty. She understands that we must raise the minimum wage to a living wage. And she is determined to create millions of new jobs by rebuilding our crumbling infrastructure – our roads, bridges, water systems and wastewater plants.

But her opponent – Donald Trump – well, he has a very different view. He does not support raising the federal minimum wage of $7.25 an hour – a starvation wage. While Donald Trump believes in huge tax breaks for billionaires, he believes that states should actually have the right to lower the minimum wage below $7.25. What an outrage!

This election is about overturning Citizens United, one of the worst Supreme Court decisions in the history of our country. That decision allows the wealthiest people in America, like the billionaire Koch brothers, to spend hundreds of millions of dollars buying elections and, in the process, undermine American democracy.

Hillary Clinton will nominate justices to the Supreme Court who are prepared to overturn Citizens United and end the movement toward oligarchy in this country. Her Supreme Court appointments will also defend a woman’s right to choose, workers’ rights, the rights of the LGBT community, the needs of minorities and immigrants and the government’s ability to protect the environment.

If you don’t believe this election is important, if you think you can sit it out, take a moment to think about the Supreme Court justices that Donald Trump would nominate and what that would mean to civil liberties, equal rights and the future of our country.

This election is about the thousands of young people I have met who have left college deeply in debt, and the many others who cannot afford to go to college. During the primary campaign, Secretary Clinton and I both focused on this issue but with different approaches. Recently, however, we have come together on a proposal that will revolutionize higher education in America. It will guarantee that the children of any family this country with an annual income of $125,000 a year or less – 83 percent of our population – will be able to go to a public college or university tuition free. That proposal also substantially reduces student debt.

This election is about climate change, the greatest environmental crisis facing our planet, and the need to leave this world in a way that is healthy and habitable for our kids and future generations. Hillary Clinton is listening to the scientists who tell us that – unless we act boldly and transform our energy system in the very near future – there will be more drought, more floods, more acidification of the oceans, more rising sea levels. She understands that when we do that we can create hundreds of thousands of good-paying jobs.

Donald Trump? Well, like most Republicans, he chooses to reject science. He believes that climate change is a "hoax," no need to address it. Hillary Clinton understands that a president’s job is to worry about future generations, not the short-term profits of the fossil fuel industry.

This campaign is about moving the United States toward universal health care and reducing the number of people who are uninsured or under-insured. Hillary Clinton wants to see that all Americans have the right to choose a public option in their health care exchange. She believes that anyone 55 years or older should be able to opt in to Medicare and she wants to see millions more Americans gain access to primary health care, dental care, mental health counseling and low-cost prescription drugs through a major expansion of community health centers.

And what is Donald Trump’s position on health care? No surprise there. Same old, same old Republican contempt for working families. He wants to abolish the Affordable Care Act, throw 20 million people off of the health insurance they currently have and cut Medicaid for lower-income Americans.

Hillary Clinton also understands that millions of seniors, disabled vets and others are struggling with the outrageously high cost of prescription drugs and the fact that Americans pay the highest prices in the world for their medicine. She knows that Medicare must negotiate drug prices with the pharmaceutical industry and that drug companies should not be making billions in profits while one in five Americans are unable to afford the medicine they need. The greed of the drug companies must end.

This election is about the leadership we need to pass comprehensive immigration reform and repair a broken criminal justice system. It’s about making sure that young people in this country are in good schools and at good jobs, not in jail cells. Hillary Clinton understands that we have to invest in education and jobs for our young people, not more jails or incarceration.

In these stressful times for our country, this election must be about bringing our people together, not dividing us up. While Donald Trump is busy insulting one group after another, Hillary Clinton understands that our diversity is one of our greatest strengths. Yes. We become stronger when black and white, Latino, Asian-American, Native American – all of us – stand together. Yes. We become stronger when men and women, young and old, gay and straight, native born and immigrant fight to create the kind of country we all know we can become.

Click on 13:12 if you want to hear him say this on the video!___

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2016-07-25 15:39:23 (0 comments; 21 reshares; 82 +1s; )Open 

Endorsed by Putin

Putin, eager to weaken the EU and NATO, has been backing right-wing demagogues throughout Europe.   So it came as no surprise when he started complimenting Trump.  Not only is Trump would-be strongman of Putin's ilk (only less clever), he's also been threatening to break US commitments to NATO.

In December, Putin called Trump "an outstanding and talented personality".  Trump, in a rare moment of sweetness, replied:

"It is always a great honor to be so nicely complimented by a man so highly respected within his own country and beyond."

Putin?  Respected?

Putin now appears to be backing Trump even more strongly, with Russian operatives hacking into Democratic National Committee (DNC) computers and trying to embarrass them shortly before the convention.

On June 14th, thecybe... more »

Endorsed by Putin

Putin, eager to weaken the EU and NATO, has been backing right-wing demagogues throughout Europe.   So it came as no surprise when he started complimenting Trump.  Not only is Trump would-be strongman of Putin's ilk (only less clever), he's also been threatening to break US commitments to NATO.

In December, Putin called Trump "an outstanding and talented personality".  Trump, in a rare moment of sweetness, replied:

"It is always a great honor to be so nicely complimented by a man so highly respected within his own country and beyond."

Putin?  Respected?

Putin now appears to be backing Trump even more strongly, with Russian operatives hacking into Democratic National Committee (DNC) computers and trying to embarrass them shortly before the convention.

On June 14th, the cybersecurity firm CrowdStrike, under contract with the DNC, announced in a blog post that two separate Russian intelligence groups had gained access to the DNC network.  One, called FANCY BEAR or APT 28, gained access in April. The other, COZY BEAR or APT 29, first breached the network in the summer of 2015.

You can read a more detailed analysis here:

https://www.crowdstrike.com/blog/bears-midst-intrusion-democratic-national-committee/

Let me quote some:

CrowdStrike Services Inc., our Incident Response group, was called by the Democratic National Committee (DNC), the formal governing body for the US Democratic Party, to respond to a suspected breach. We deployed our IR team and technology and immediately identified two sophisticated adversaries on the network – COZY BEAR and FANCY BEAR. We’ve had lots of experience with both of these actors attempting to target our customers in the past and know them well. In fact, our team considers them some of the best adversaries out of all the numerous nation-state, criminal and hacktivist/terrorist groups we encounter on a daily basis. Their tradecraft is superb, operational security second to none and the extensive usage of ‘living-off-the-land’ techniques enables them to easily bypass many security solutions they encounter. In particular, we identified advanced methods consistent with nation-state level capabilities including deliberate targeting and ‘access management’ tradecraft – both groups were constantly going back into the environment to change out their implants, modify persistent methods, move to new Command & Control channels and perform other tasks to try to stay ahead of being detected. Both adversaries engage in extensive political and economic espionage for the benefit of the government of the Russian Federation and are believed to be closely linked to the Russian government’s powerful and highly capable intelligence services.

COZY BEAR (also referred to in some industry reports as CozyDuke or APT 29) is the adversary group that last year successfully infiltrated the unclassified networks of the White House, State Department, and US Joint Chiefs of Staff. In addition to the US government, they have targeted organizations across the Defense, Energy, Extractive, Financial, Insurance, Legal, Manufacturing Media, Think Tanks, Pharmaceutical, Research and Technology industries, along with Universities. Victims have also been observed in Western Europe, Brazil, China, Japan, Mexico, New Zealand, South Korea, Turkey and Central Asian countries. COZY BEAR’s preferred intrusion method is a broadly targeted spearphish campaign that typically includes web links to a malicious dropper. Once executed on the machine, the code will deliver one of a number of sophisticated Remote Access Tools (RATs), including AdobeARM, ATI-Agent, and MiniDionis. On many occasions, both the dropper and the payload will contain a range of techniques to ensure the sample is not being analyzed on a virtual machine, using a debugger, or located within a sandbox. They have extensive checks for the various security software that is installed on the system and their specific configurations. When specific versions are discovered that may cause issues for the RAT, it promptly exits. These actions demonstrate a well-resourced adversary with a thorough implant-testing regime that is highly attuned to slight configuration issues that may result in their detection, and which would cause them to deploy a different tool instead. The implants are highly configurable via encrypted configuration files, which allow the adversary to customize various components, including C2 servers, the list of initial tasks to carry out, persistence mechanisms, encryption keys and others. An HTTP protocol with encrypted payload is used for the Command & Control communication.

FANCY BEAR (also known as Sofacy or APT 28) is a separate Russian-based threat actor, which has been active since mid 2000s, and has been responsible for targeted intrusion campaigns against the Aerospace, Defense, Energy, Government and Media sectors. Their victims have been identified in the United States, Western Europe, Brazil, Canada, China, Georgia, Iran, Japan, Malaysia and South Korea. Extensive targeting of defense ministries and other military victims has been observed, the profile of which closely mirrors the strategic interests of the Russian government, and may indicate affiliation with Главное Разведывательное Управление (Main Intelligence Department) or GRU, Russia’s premier military intelligence service. This adversary has a wide range of implants at their disposal, which have been developed over the course of many years and include Sofacy, X-Agent, X-Tunnel, WinIDS, Foozer and DownRange droppers, and even malware for Linux, OSX, IOS, Android and Windows Phones. This group is known for its technique of registering domains that closely resemble domains of legitimate organizations they plan to target. Afterwards, they establish phishing sites on these domains that spoof the look and feel of the victim’s web-based email services in order to steal their credentials. FANCY BEAR has also been linked publicly to intrusions into the German Bundestag and France’s TV5 Monde TV station in April 2015.

At DNC, COZY BEAR intrusion has been identified going back to summer of 2015, while FANCY BEAR separately breached the network in April 2016. We have identified no collaboration between the two actors, or even an awareness of one by the other. Instead, we observed the two Russian espionage groups compromise the same systems and engage separately in the theft of identical credentials. While you would virtually never see Western intelligence agencies going after the same target without de-confliction for fear of compromising each other’s operations, in Russia this is not an uncommon scenario. “Putin’s Hydra: Inside Russia’s Intelligence Services”, a recent paper from European Council on Foreign Relations, does an excellent job outlining the highly adversarial relationship between Russia’s main intelligence services – Федеральная Служба Безопасности (FSB), the primary domestic intelligence agency but one with also significant external collection and ‘active measures’ remit, Служба Внешней Разведки (SVR), the primary foreign intelligence agency, and the aforementioned GRU. Not only do they have overlapping areas of responsibility, but also rarely share intelligence and even occasionally steal sources from each other and compromise operations. Thus, it is not surprising to see them engage in intrusions against the same victim, even when it may be a waste of resources and lead to the discovery and potential compromise of mutual operations.

You can even see some of the code that was used. Another security group, Fidelis, did an independent study confirming CrowdStriker's findings:

http://www.threatgeek.com/2016/06/dnc_update.html

Of course, none of this excuses the DNC's dastardly behavior as revealed by the hacked emails.  But it's another sign of how sickening a disaster a Trump presidency would be.

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Putin's compliment, and Trump's reply, is here:

http://www.cnn.com/2015/12/17/politics/russia-putin-trump/

Here's an article on Putin's "useful idiots" in Europe:

http://foreignpolicy.com/2016/02/23/why-europe-is-right-to-fear-putins-useful-idiots/

A quote, which contains lots of links in the original:

Prior to 2010, one would be hard-pressed to find public statements in praise of Putin by far-right leaders. Today, they are commonplace. UKIP’s Nigel Farage is a self-proclaimed fan of the Russian president. Jobbik’s head, Gabor Vona, is a frequent invited guest in Moscow. And, of course, Madame Le Pen, whose party was the beneficiary of a 9.4 million euro loan from a Russian-owned bank, is a consistent voice of support for Russian foreign policy in Ukraine and the Middle East. Even Germany, where the far right has failed to gain a foothold, is not immune to Moscow’s narrative. Supporters of PEGIDA, the increasingly popular xenophobic group whose acronym stands for “Patriotic Europeans Against the Islamization of the West,” often carry Russian flags and anti-government posters begging for Putin’s help.___

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2016-07-24 04:19:04 (13 comments; 10 reshares; 77 +1s; )Open 

New kinds of quasiparticles

You can get electrons to behave in many strange ways in different materials.   They act like various kinds of particles... but they're not truly fundamental particles, so they're called quasiparticles

For example, the spin, charge and position of electrons can move in completely independent ways. 

Imagine an audience at a football game holding up signs, and then creating a wave by wiggling their signs.  This wave can move even even if the people stand still! 

Similarly, we can have electrons more or less standing still, with their spins lined up.   Then their spins can wiggle a bit, and this wiggle can move through the material, even though the electrons don't move.  This wave of altered spin can act like a particle!  It's called a spinon.

You can also imagine a hole in a densecrowd of... more »

New kinds of quasiparticles

You can get electrons to behave in many strange ways in different materials.   They act like various kinds of particles... but they're not truly fundamental particles, so they're called quasiparticles

For example, the spin, charge and position of electrons can move in completely independent ways. 

Imagine an audience at a football game holding up signs, and then creating a wave by wiggling their signs.  This wave can move even even if the people stand still! 

Similarly, we can have electrons more or less standing still, with their spins lined up.   Then their spins can wiggle a bit, and this wiggle can move through the material, even though the electrons don't move.  This wave of altered spin can act like a particle!  It's called a spinon.

You can also imagine a hole in a dense crowd of people, moving along as if it were an entity of its own.  When this happens with electrons it's called a holon, or more commonly just a hole.  A hole acts like a particle with positive charge, since electrons have negative charge. 

Since holes have positive charge and electrons have negative charge, they attract.   Sometimes they orbit each other for long enough that this combined thing acts like a particle of its own!   This kind of quasiparticle is called an exciton.

There are also other quasiparticles.  If you're a student who wants to do particle physics, please switch to studying quasiparticles!  The math is almost the same, and you don't need huge particle accelerators to make cool new discoveries.  Some are even useful.

One of the most fundamental things about a quasiparticle, or for that matter an ordinary particle, is its energy.  Its energy depends on its momentum.  The relation between them is called the dispersion relation.  This says a lot about how the quasiparticle acts.

Right next door to the +Centre for Quantum Technologies where I'm working in Singapore, there's a lab that specializes in graphene - a crystal made of carbon that's just one atom thick.  When you've got a very thin film like this, a quasiparticle inside it acts like it's living in a 2-dimensional world!   Since it can't go up and down, only 2 components of its momentum can be nonzero.

The picture here shows a graph of energy as a function of momentum for a new kind of quasiparticle they're studying.  They haven't made it in the lab yet; they've just shown it's possible. 

The three colored sheets show that 3 different energies are possible for each momentum - except momentum zero, where all three sheet meet, and also a line of momenta where two sheets meet.

If we only had the green and blue sheets, that would be the dispersion relation for a massless particle.  People already know how to make massless quasiparticles with graphene.

The new thing is the yellow sheet!  This will make very strange things happen, I'm sure.

I got interested in these new quasiparticles thanks to this article pointed out by +rasha kamel:

• Unconventional quasiparticles predicted in conventional crystals, ScienceDaily, https://www.sciencedaily.com/releases/2016/07/160721151219.htm

But I got the picture from here:

• Guoqing Chang et al, New fermions on the line in topological symmorphic metals, http://arxiv.org/abs/1605.06831.

Here's the abstract, for you physics nerds out there:

Abstract. Topological metals and semi-metals (TMs) have recently drawn significant interest. These materials give rise to condensed matter realizations of many important concepts in high-energy physics, leading to wide-ranging protected properties in transport and spectroscopic experiments. The most studied TMs, i.e., Weyl and Dirac semi-metals, feature quasiparticles that are direct analogues of the textbook elementary particles. Moreover, the TMs known so far can be characterized based on the dimensionality of the band crossing. While Weyl and Dirac semimetals feature zero-dimensional points, the band crossing of nodal-line semimetals forms a one-dimensional closed loop. In this paper, we identify a TM which breaks the above paradigms. Firstly, the TM features triply-degenerate band crossing in a symmorphic lattice, hence realizing emergent fermionic quasiparticles not present in quantum field theory. Secondly, the band crossing is neither 0D nor 1D. Instead, it consists of two isolated triply-degenerate nodes interconnected by multi-segments of lines with two-fold degeneracy. We present materials candidates. We further show that triply-degenerate band crossings in symmorphic crystals give rise to a Landau level spectrum distinct from the known TMs, suggesting novel magneto-transport responses. Our results open the door for realizing new topological phenomena and fermions including transport anomalies and spectroscopic responses in metallic crystals with nontrivial topology beyond the Weyl/Dirac paradigm.

Weirdly, I had learned the word 'symmorphic' just yesterday.  Greg Egan are writing a paper on crystals, and he explained that a crystal is symmorphic if it contains a point where every symmetry of the crystal consists of a symmetry fixing this point followed by a translation.   It was important for our work to notice that a diamond is not symmorphic.

#spnetwork arXiv:1605.06831 #condensedMatter #physics  ___

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2016-07-23 02:54:41 (22 comments; 4 reshares; 43 +1s; )Open 

The quest for larger infinities

There are different kinds of bigness.   But they're connected.

There's a fascinating contest where you try to write the computer program of a certain length that would print out the largest possible integer.    This contest was actually carried out on the xkcd blog, and Eliezer Yudkowsky won.  Unless you know more about logic than he does, you won't be able to beat him.

There's another contest where you try to name the largest "computable ordinal", and that's what my post is about:

https://johncarlosbaez.wordpress.com/2016/07/07/large-countable-ordinals-part-3/

And there's another contest where you try to name the largest "cardinal".   Here we get into inaccessible cardinals, indescribable cardinals, huge cardinals, superhuge cardinals and the like. 
But th... more »

The quest for larger infinities

There are different kinds of bigness.   But they're connected.

There's a fascinating contest where you try to write the computer program of a certain length that would print out the largest possible integer.    This contest was actually carried out on the xkcd blog, and Eliezer Yudkowsky won.  Unless you know more about logic than he does, you won't be able to beat him.

There's another contest where you try to name the largest "computable ordinal", and that's what my post is about:

https://johncarlosbaez.wordpress.com/2016/07/07/large-countable-ordinals-part-3/

And there's another contest where you try to name the largest "cardinal".   Here we get into inaccessible cardinals, indescribable cardinals, huge cardinals, superhuge cardinals and the like. 

But these three contests turn out to deeply related!   There's a way to name huge integers using fast-growing functions that you can describe using large computable ordinals.  And Yudkowsky won the contest to write a program that prints out a large integer by taking advantage of a very large cardinal.

So, there's a spooky connection between large finite numbers, large computable ordinals - which are all countable, by the way - and large cardinals, which are not countable.  Many theorems point at this connection, but the full story remains obscure.  I believe when it becomes clear we'll get a whole new idea of what the infnite is all about.

As for me, I need a break.  My post takes you up to the large Veblen ordinal, a whopping large computable ordinal... but I know people have studied others that dwarf this one.  As Bilbo said:

The Road goes ever on and on
Out from the door where it began.
Now far ahead the Road has gone,
Let others follow it who can!
Let them a journey new begin,
But I at last with weary feet
Will turn towards the lighted inn,
My evening-rest and sleep to meet.

#bigness  ___

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2016-07-21 23:28:18 (0 comments; 18 reshares; 102 +1s; )Open 

Republicans for Trump

Cruz caused a stir at the Republican convention by not endorsing Trump.  But here's what other Republicans say:

“He’s a race-baiting, xenophobic religious bigot. He doesn’t represent my party. He doesn’t represent the values that the men and women who wear the uniform are fighting for.” — Senator Lindsey Graham, Republican of South Carolina

“I don’t think this guy has any more core principles than a Kardashian marriage.” — Senator Ben Sasse, Republican of Nebraska

“We saw and looked at true hate in the eyes last year in Charleston. I will not stop until we fight a man that chooses not to disavow the K.K.K. That is not a part of our party.” — Nikki Haley, Republican governor of South Carolina

“Donald Trump is a madman who must be stopped,” — Bobby Jindal, former Republican governor ofLouisiana

“I won’t vo... more »

Republicans for Trump

Cruz caused a stir at the Republican convention by not endorsing Trump.  But here's what other Republicans say:

“He’s a race-baiting, xenophobic religious bigot. He doesn’t represent my party. He doesn’t represent the values that the men and women who wear the uniform are fighting for.” — Senator Lindsey Graham, Republican of South Carolina

“I don’t think this guy has any more core principles than a Kardashian marriage.” — Senator Ben Sasse, Republican of Nebraska

“We saw and looked at true hate in the eyes last year in Charleston. I will not stop until we fight a man that chooses not to disavow the K.K.K. That is not a part of our party.” — Nikki Haley, Republican governor of South Carolina

“Donald Trump is a madman who must be stopped,” — Bobby Jindal, former Republican governor of Louisiana

“I won’t vote for Donald Trump because of who he isn’t. He isn’t a Republican. He isn’t a conservative. He isn’t a truth teller. ... I also won’t vote for Donald Trump because of who he is. A bigot. A misogynist. A fraud. A bully.” — Norm Coleman, former Republican senator from Minnesota

“To support Trump is to support a bigot. It’s really that simple.” — Stuart Stevens, chief strategist to Mitt Romney’s 2012 presidential campaign

“Donald Trump is unfit to be president. He is a dishonest demagogue who plays to our worst fears. Trump would take America on a dangerous journey.” — Meg Whitman, Hewlett-Packard Enterprise C.E.O. and former national finance co-chairwoman for Chris Christie’s presidential campaign

“I thought he was an embarrassment to my party; I think he’s an embarrassment to my country. … I can’t vote for him.” — Tom Ridge, former Republican governor of Pennsylvania and secretary of homeland security under George W. Bush

“I would not vote for Trump, clearly. If there is any, any, any other choice, a living, breathing person with a pulse, I would be there.” — Mel Martinez, former Republican senator from Florida and former chairman of the Republican National Committee

“The G.O.P., in putting Trump at the top of the ticket, is endorsing a brand of populism rooted in ignorance, prejudice, fear and isolationism. This troubles me deeply as a Republican, but it troubles me even more as an American. … Never Trump.” — Henry M. Paulson Jr., Treasury secretary under George W. Bush

“Donald Trump is a phony, a fraud. His promises are as worthless as a degree from Trump University.” — Mitt Romney, 2012 Republican nominee for president

“When you’ve got a guy favorably quoting Mussolini, I don’t care what party you’re in, I’m not voting for that guy.” — Ken Cuccinelli, president of the Senate Conservatives Fund

“Donald Trump is a scam. Evangelical voters should back away... Trump is a misogynist and philanderer. He demeans women and minorities. His preferred forms of communication are insults, obscenities and untruths.” — The Christian Post, a popular U.S. evangelical website

“A moral degenerate.” — Peter Wehner, evangelical Christian commentator who served in last three Republican administrations

“A man utterly unfit for the position by temperament, values and policy preferences … whose personal record of chicanery and wild rhetoric of bigotry, misogyny and misplaced belligerence are without parallel in the modern history of either major party.” — Eliot A. Cohen, a senior State Department official under George W. Bush

“Leaders don’t need to do research to reject Klan support. #NeverTrump” — Ken Mehlman, former chairman of the Republican National Committee

“God bless this man” — Daily Stormer, white supremacist website

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Sources for all these quotes can be found by clicking on the links here:

http://www.nytimes.com/2016/07/21/opinion/what-republicans-really-think-about-trump.html___

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2016-07-19 02:19:16 (13 comments; 11 reshares; 70 +1s; )Open 

Into the clouds

Frigatebirds are amazing:

Ornithologist Henri Weimerskirch put satellite tags on a couple of dozen frigatebirds, as well as instruments that measured body functions such as heart rate. When the data started to come in, he could hardly believe how high the birds flew.

“First, we found, ‘Whoa, 1,500 meters. Wow. Excellent, fantastique,’ ” says Weimerskirch, who is with the National Center for Scientific Research in Paris. “And after 2,000, after 3,000, after 4,000 meters — OK, at this altitude they are in freezing conditions, especially surprising for a tropical bird.”

Four thousand meters is more than 12,000 feet, or as high as parts of the Rocky Mountains. “There is no other bird flying so high relative to the sea surface,” he says.

Weimerskirch says that kind of flying should take a hugeamount of energy.... more »

Into the clouds

Frigatebirds are amazing:

Ornithologist Henri Weimerskirch put satellite tags on a couple of dozen frigatebirds, as well as instruments that measured body functions such as heart rate. When the data started to come in, he could hardly believe how high the birds flew.

“First, we found, ‘Whoa, 1,500 meters. Wow. Excellent, fantastique,’ ” says Weimerskirch, who is with the National Center for Scientific Research in Paris. “And after 2,000, after 3,000, after 4,000 meters — OK, at this altitude they are in freezing conditions, especially surprising for a tropical bird.”

Four thousand meters is more than 12,000 feet, or as high as parts of the Rocky Mountains. “There is no other bird flying so high relative to the sea surface,” he says.

Weimerskirch says that kind of flying should take a huge amount of energy. But the instruments monitoring the birds’ heartbeats showed that the birds weren’t even working up a sweat. (They wouldn’t, actually, since birds don’t sweat, but their heart rate wasn’t going up.)

How did they do it? By flying into a cloud.

“It’s the only bird that is known to intentionally enter into a cloud,” Weimerskirch says. And not just any cloud—a fluffy, white cumulus cloud. Over the ocean, these clouds tend to form in places where warm air rises from the sea surface. The birds hitch a ride on the updraft, all the way up to the top of the cloud.

But this is far from the only amazing thing about frigatebirds!  For the full story, read this:

https://johncarlosbaez.wordpress.com/2016/07/18/frigatebirds/

You'll also learn the dark side of frigatebirds: they're kleptoparasites.

The quote is from here:

• Christopher Joyce, Nonstop flight: how the frigatebird can soar for weeks without stopping, All Things Considered, National Public Radio, 30 June 2016, http://www.npr.org/sections/thetwo-way/2016/06/30/484164544/non-stop-flight-how-the-frigatebird-can-soar-for-months-without-stopping

and the photo is from here:

https://www.pinterest.com/pin/237353842833650981/

#biology  ___

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2016-07-16 00:51:06 (25 comments; 4 reshares; 72 +1s; )Open 

A winning septic

A septic tank is a system for disposing of sewage.  A septic surface is a surface described by a polynomial equation of degree 7.

This picture by +Abdelaziz Nait Merzouk shows a septic surface discovered by Oliver Labs when he was working on his PhD thesis. 

It looks like a beautiful flower of some strange sort.  But it's famous because it's the septic with the largest known number of points that look like two cones meeting tip to tip. 

How many?  Ninety-nine!  We know that no septic can have more than 104 of these ordinary double points, as they're called.  But we don't know any with more than 99.  So this is currently one of the winners.  There are others, too, also discovered by Labs.

This surface is called the Labs septic, which reminds me of yet another meaning of the word'sep... more »

A winning septic

A septic tank is a system for disposing of sewage.  A septic surface is a surface described by a polynomial equation of degree 7.

This picture by +Abdelaziz Nait Merzouk shows a septic surface discovered by Oliver Labs when he was working on his PhD thesis. 

It looks like a beautiful flower of some strange sort.  But it's famous because it's the septic with the largest known number of points that look like two cones meeting tip to tip. 

How many?  Ninety-nine!  We know that no septic can have more than 104 of these ordinary double points, as they're called.  But we don't know any with more than 99.  So this is currently one of the winners.  There are others, too, also discovered by Labs.

This surface is called the Labs septic, which reminds me of yet another meaning of the word 'septic'.  

Sepsis occurs when harmful bacteria start to grow in tissue.  So, 'septic' also means 'infected with bacteria'... and 'Labs septic' has a strangely medical sound.   But this septic is pure and beautiful.

For more on how the Labs septic was found, and another view of it, visit my blog Visual Insight:

http://blogs.ams.org/visualinsight/2016/07/15/labs-septic/

#geometry  ___

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2016-07-12 04:25:39 (24 comments; 26 reshares; 92 +1s; )Open 

Global warming: demand the truth

After announcements that 2015 was the hottest year on record and February 2016 was the hottest month, the news station CNN aired five times more fossil fuel advertising than actual climate reporting!

So, please sign this petition to CNN.  Tell them: start reporting on climate change.   And please reshare this message.

A study by the group Media Matters showed that the American Petroleum Institute is getting more coverage than actual news about global warming.  This doesn't even include the ads from individual fossil fuel companies and the Koch brothers.

Here's some actual news, in case you hadn't heard:

1) The extent of Arctic sea ice in June was the lowest in recorded history for that month of the year: 260,000 square kilometers less than ever before!   It's on track to break allrecor... more »

Global warming: demand the truth

After announcements that 2015 was the hottest year on record and February 2016 was the hottest month, the news station CNN aired five times more fossil fuel advertising than actual climate reporting!

So, please sign this petition to CNN.  Tell them: start reporting on climate change.   And please reshare this message.

A study by the group Media Matters showed that the American Petroleum Institute is getting more coverage than actual news about global warming.  This doesn't even include the ads from individual fossil fuel companies and the Koch brothers.

Here's some actual news, in case you hadn't heard:

1) The extent of Arctic sea ice in June was the lowest in recorded history for that month of the year: 260,000 square kilometers less than ever before!   It's on track to break all records this year.

2) Recently every month from October until May has been the hottest on record worldwide.  June was the second hottest, since the El Niño is fading.

3) India recorded its hottest day ever on May 19th. The temperature in Phalodi hit 51 degrees Celsius (124 degrees Fahrenheit), and a nationwide drought has affected more than 300 million people marched on, leaving armed guards at dams, and reservoirs well below their usual levels.

4) Alaska, along with the rest of the Arctic, has experienced record-breaking heat this year.  Its average year-to-date temperature has been 5.5C above the long term average.

5) In the atmosphere, carbon dioxide has been increasing every year for decades - but this year the speed of increase is also record-breaking!   The increase for 2016 is expected to be 3.1 parts per million, up from an annual average of 2.1.

6) The Great Barrier Reef, a natural wonder and world heritage site, recently experienced its worst ever coral bleaching event.  An aerial study found that just 7% of the reef escaped bleaching. 

7) A new study in Nature argues that even despite the actions pledged in the Paris Agreement, the Earth is still on course for a temperature increase of 2.6 - 3.1C by the end of this century.  Read this:

http://www.nature.com/nature/journal/v534/n7609/full/nature18307.html

The Paris agreement is a step in the right direction, but we need to ratchet it up.  We can't afford to slack off now.  One piece of the puzzle is clear information about the crisis we're in.

------------------------------------------------

Media Matters writes:

In Week After Hottest Year Announcement, CNN Aired Less Than One Minute Of Climate-Related Coverage And 13.5 Minutes Of Oil Industry Ads.

From January 20 to January 26, CNN morning, daytime and primetime programming included only 57 seconds of coverage about climate change or the announcement that 2015 was the hottest year on record. Over that same time period, CNN aired 13.5 minutes of American Petroleum Institute ads. The climate-related segments included one on the January 21 edition of Early Start, in which anchor Christine Romans reported that 2015 was the hottest year on record and that officials say “the planet is still warming with no apparent change in the long term global warming rate.” Additionally, CNN senior legal analyst Jeffrey Toobin briefly mentioned Republican climate science denial during a discussion of Hillary Clinton’s emails on Anderson Cooper 360, and CNN host Fareed Zakaria noted that the “The World Economic Forum said this year that the greatest global risk is the failure of climate change mitigation and adaptation,” during a Fareed Zakaria GPS segment about a study finding that humans have entered a new geological epoch known as the Anthropocene.

Following Announcement That February 2016 Was Most Unusually Hot Month Ever, CNN Aired Four Minutes Of Climate-Related Coverage And 10 Minutes Of Fossil Fuel Ads.

In the one-week period beginning March 17, when NOAA released data showing that February 2016 was the most unusually hot month ever recorded, CNN aired only four minutes of coverage about climate change or the temperature record during its morning, daytime, and primetime coverage. During that same time period, CNN aired ten minutes of American Petroleum Institute ads. On March 18, CNN anchors Christine Romans and John Berman delivered nearly-identical reports on February’s “astounding” temperature record during the 4 a.m. and 5 a.m. editions of Early Start, respectively, but neither explicitly mentioned climate change or the role fossil fuel pollution and other human activities play in driving climate change. The March 20 edition of Fareed Zakaria GPS featured an interview with astronaut Piers Sellers about his climate change advocacy, followed by a brief report about International Energy Administration (IEA) data showing a decline in carbon emissions from energy production, which Zakaria described as “some good news on the climate front” and a “welcome update in the climate battle.” Finally, on the March 20 edition of New Day Sunday, anchor Christi Paul reported that major cities around the world were participating in Earth Hour, an event meant to bring awareness to climate change, by switching off their lights.

For more details see:

http://mediamatters.org/research/2016/04/25/study-cnn-viewers-see-far-more-fossil-fuel-advertising-climate-change-reporting/209985

Here's the data for the statements 1)-6):

https://www.theguardian.com/environment/2016/jun/17/seven-climate-records-set-so-far-in-2016

https://www.theguardian.com/environment/2016/jul/07/arctic-sea-ice-crashes-to-record-low-for-june

http://www.netnewsledger.com/2016/07/05/june-2016-second-hottest-june-ever/___

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2016-07-10 15:13:26 (44 comments; 24 reshares; 127 +1s; )Open 

Gimbal lock

Here you see 3 rotating rings called gimbals.  Gimbals are used in gyroscopes and inertial measurement units, which are gadgets that measure an object's orientation - like a drone, or a spacecraft.   Gimbals are also used to orient thrusters on rockets.

With 3 gimbals, you can rotate the inner one to whatever orientation you want.  The basic reason is that it takes 3 numbers to describe a rotation in 3 dimensional space.  This is a special lucky property of the number 3. 

But when two of the gimbal's axes happen to be lined up, you get gimbal lock.   In other words: you lose the ability to rotate the inner gimbal a tiny bit in any way you want.   The reason is that in this situation, rotating one of the two aligned gimbals has the same effect on the inner gimbal as rotating the other!  

I've always foundgimbal lock... more »

Gimbal lock

Here you see 3 rotating rings called gimbals.  Gimbals are used in gyroscopes and inertial measurement units, which are gadgets that measure an object's orientation - like a drone, or a spacecraft.   Gimbals are also used to orient thrusters on rockets.

With 3 gimbals, you can rotate the inner one to whatever orientation you want.  The basic reason is that it takes 3 numbers to describe a rotation in 3 dimensional space.  This is a special lucky property of the number 3. 

But when two of the gimbal's axes happen to be lined up, you get gimbal lock.   In other words: you lose the ability to rotate the inner gimbal a tiny bit in any way you want.   The reason is that in this situation, rotating one of the two aligned gimbals has the same effect on the inner gimbal as rotating the other!  

I've always found gimbal lock to be a bit mysterious, so I'm trying to demystify it here. 

As the wise heads at Wikipedia point out,

The word lock is misleading: no gimbal is restrained. All three gimbals can still rotate freely about their respective axes of suspension. Nevertheless, because of the parallel orientation of two of the gimbals' axes there is no gimbal available to accommodate rotation along one axis.

Gimbal lock can actually be dangerous!  When it happens, or even when it almost happens, you lose some control over what's going on.

It caused a problem when Apollo 11 was landing on the moon.  This spacecraft had 3 nested gimbals on its inertial measurement unit. The engineers were aware of the gimbal lock problem but decided not to use a fourth gimbal.  They wrote:

"The advantages of the redundant gimbal seem to be outweighed by the equipment simplicity, size advantages, and corresponding implied reliability of the direct three degree of freedom unit."

They decided instead to trigger a warning when the system came close to gimbal lock.  But it didn't work right:

"Near that point, in a closed stabilization loop, the torque motors could theoretically be commanded to flip the gimbal 180 degrees instantaneously. Instead, in the Lunar Module, the computer flashed a 'gimbal lock' warning at 70 degrees and froze the inertial measurment unit at 85 degrees."

The spacecraft had to be manually moved away from the gimbal lock position, and they had to start over from scratch, using the stars as a reference.

After the Lunar Module had landed, Mike Collins aboard the Command Module joked:

"How about sending me a fourth gimbal for Christmas?"

Fun story!  But ultimately, it's all about math.  If you don't like math, stop reading here.

























Don't say I didn't warn you!

Puzzle: show that gimbal lock is inevitable with just 3 gimbals by showing that every smooth map from the 3-torus to SO(3) has at least one point where the rank of its differential drops below 3.

See what I mean?  Math.  This result shows not only that gimbal lock occurs with the setup shown here, but that any scheme of describing a rotation by 3 angles - or more precisely, 3 points on the circle - must suffer gimbal lock.

https://en.wikipedia.org/wiki/Gimbal_lock

#geometry___

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2016-07-08 08:08:55 (11 comments; 1 reshares; 43 +1s; )Open 

Adventures in Asia

I'm back in Singapore, the land of explosive cuisine.  This is the menu from our favorite Chinese restaurant.  It's on Southbridge Road across from the Sri Mariamman Temple - a popular Hindu temple where they do firewalking on the holiday called Theemithi.  Maybe they do it to cool down after eating here. 

I hadn't known it was called The Explosion Pot Barbecue.  They sell excellent barbecued fish, roast skewers of lamb with cumin, roast chives, dumplings, and other Szechuan delights.  The food is a bit spicy, but I haven't seen any exploding pots, so this may be a mistranslation of something that makes more sense in Chinese. 

As usual I'm working at the +Centre for Quantum Technologies and my wife +Lisa Raphals is teaching at the philosophy department at NUS.  You can see her in the background ordering ourfood.more »

Adventures in Asia

I'm back in Singapore, the land of explosive cuisine.  This is the menu from our favorite Chinese restaurant.  It's on Southbridge Road across from the Sri Mariamman Temple - a popular Hindu temple where they do firewalking on the holiday called Theemithi.  Maybe they do it to cool down after eating here. 

I hadn't known it was called The Explosion Pot Barbecue.  They sell excellent barbecued fish, roast skewers of lamb with cumin, roast chives, dumplings, and other Szechuan delights.  The food is a bit spicy, but I haven't seen any exploding pots, so this may be a mistranslation of something that makes more sense in Chinese. 

As usual I'm working at the +Centre for Quantum Technologies and my wife +Lisa Raphals is teaching at the philosophy department at NUS.  You can see her in the background ordering our food.

Meanwhile, my student +Blake Pollard is in a small town in the hills of Yunnan Province in southern China, helping teach some local students science, English... and American folk songs!  

This seems much more adventurous than what I'm doing.  But he has a good reason for doing it.   His great grandfather, Sam Pollard, was a Methodist missionary in this area - and he invented a script that is still used by the locals:

https://en.wikipedia.org/wiki/Pollard_script

The Miao are an ethnic group that includes the Hmong, Hmub, Xong, and A-Hmao.  These folks live in the borderlands of southern China, northern Vietnam, Laos, Myanmar and Thailand.  The A-Hmao had a legend about how their ancestors knew a system of writing but lost it. According to this legend, the script would eventually be brought back some day.  When Sam Pollard introduced his script for writing A-Hmao, it became extremely popular, and he became a kind of hero.  Blake and his family visited this part of China last year.  He enjoyed it a lot, so he decided to do some teaching there this summer. 

I hope to say more about both our adventures in a while...

Watch firewalking at the Sri Mariamman Temple:

https://www.youtube.com/watch?v=nxPuTKx3OEI

and if you live around here, check out the Explosion Pot Barbecue:

https://www.google.com/maps?daddr=1.282462,103.845405___

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2016-07-07 02:51:27 (35 comments; 44 reshares; 226 +1s; )Open 

Sugihara's illusion explained

Wow!  These plastic cylinders look round - but in the mirror they look diamond-shaped.  If you turn them around, they look diamond-shaped - but in the mirror they look round!

This video was made by Kokichi Sugihara, an engineer at Meiji University in Tokyo.  How did he do it???

To answer this question, we should "science the hell out of it", as Matt Damon said in The Martian.   Figure out how objects change appearance when you look at them in a mirror... and design an object that does this!

So +David Richeson scienced the hell out of it:

https://divisbyzero.com/2016/07/05/sugiharas-circlesquare-optical-illusion/

The basic idea is this.  The top rim of this object is not flat.  More precisely, it's not horizontal: it curves up and down!  This affects how it looks.  If you'relooking ... more »

Sugihara's illusion explained

Wow!  These plastic cylinders look round - but in the mirror they look diamond-shaped.  If you turn them around, they look diamond-shaped - but in the mirror they look round!

This video was made by Kokichi Sugihara, an engineer at Meiji University in Tokyo.  How did he do it???

To answer this question, we should "science the hell out of it", as Matt Damon said in The Martian.   Figure out how objects change appearance when you look at them in a mirror... and design an object that does this!

So +David Richeson scienced the hell out of it:

https://divisbyzero.com/2016/07/05/sugiharas-circlesquare-optical-illusion/

The basic idea is this.  The top rim of this object is not flat.  More precisely, it's not horizontal: it curves up and down!  This affects how it looks.  If you're looking down on this object, you can make part of the top look farther away  by having it be lower. 

But a mirror reflects front and back.   So in the mirror, part of the top looks closer  if it's lower.

By cleverly taking advantage of this, we can make this object look round, but diamond-shaped in the mirror. 

And if we turn it around, this effect is reversed!

Here's a bit more of the math.  +David Richeson gives the details, so I'll try to present just the basic idea. 

Suppose you're making a video.  Suppose you're looking down at an angle of 45 degrees, just as in this video.   Suppose you're videotaping an object that's fairly far away.

Think about one pixel of the object's image on your camera's viewscreen.

Its height on your viewscreen depends on two things.  It depends on how far up  that piece of the object actually is.  But it also depends on how far back  that piece of the object is: how far away it is from your camera.   Things farther away give higher pixels on your viewscreen.

There's a simple formula for how this works:

pixel height = actual object height + actual distance back

(It's only this simple when you're looking down at an angle of 45 degrees and the thing you're videotaping is fairly far away.)

But what if we're looking in a mirror?  You may think a mirror reverses left and right, but that's wrong: it reverses front and back.  So we basically get
 
mirror image pixel height = actual object height - actual distance back

So, you just need to craft an object for which

actual object height + actual distance back

and

actual object height - actual distance back

give two different curves: one round and one a diamond!

But now for some puzzles:

Puzzle 1.  All that sounds fine: by cleverly adjusting the top rim of the object we can make it look different in a mirror.  But look at the bottom of the object!   What's going on there?  How do you explain that?

Puzzle 2.  Sometimes I know the answers to the puzzles I'm posing.  Sometimes I don't.   Do I know the answer to Puzzle 1, or not?

Puzzle 3.  Same question for Puzzle 2.

Finally, I should admit that I simplified the formula for the mirror image pixel height.  Actually we have

mirror image distance back = constant - actual distance back

and thus

mirror image pixel height =
actual object height + mirror image distance back =
actual object height + constant - actual distance back

In other words, I ignored a constant.  This constant is why the whole mirror image looks higher on your viewscreen than the original object!___

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2016-07-06 02:10:25 (31 comments; 16 reshares; 104 +1s; )Open 

♥ ♥ ♥ I love infinity ♥ ♥ ♥

Some infinities are countable, like the number of integers.  Others are uncountable, like the number of points on a line. 

Uncountable infinities are hard to fully comprehend.  For example, even if you think an infinity is uncountable, someone else may consider it countable!  That's roughly what the Löwenheim–Skolem theorem says. 

How is this possible? 

Ultimately, it's because there are only a countable number of sentences in any language with finitely many letters.  So, no matter how much you talk, you can never convince me that you're talking about something uncountable!
 
Now, if we take a really hard-ass attitude, we have to admit we can never actually write infinitely many sentences.   So even countable infinities remain outside our grasp.   However, we come "asclose as we want", i... more »

♥ ♥ ♥ I love infinity ♥ ♥ ♥

Some infinities are countable, like the number of integers.  Others are uncountable, like the number of points on a line. 

Uncountable infinities are hard to fully comprehend.  For example, even if you think an infinity is uncountable, someone else may consider it countable!  That's roughly what the Löwenheim–Skolem theorem says. 

How is this possible? 

Ultimately, it's because there are only a countable number of sentences in any language with finitely many letters.  So, no matter how much you talk, you can never convince me that you're talking about something uncountable!
 
Now, if we take a really hard-ass attitude, we have to admit we can never actually write infinitely many sentences.   So even countable infinities remain outside our grasp.   However, we come "as close as we want", in the sense that we can keep counting

0, 1, 2, 3, 4,  ...

and nothing seems to stop us.  So, while we never actually reach the countably infinite, it's pretty easy to imagine and work with. 

Thus, my favorite infinities are the countable ordinals - in particular, the computable ones.   You can learn to do arithmetic with them.  You can learn to visualize them just as vividly as the set of all natural numbers, which is the first countable ordinal:

ω = {0,1,2,3,4,5,6,7,8,9,...}

For example,

ω+1 = {0,1,2,3,4,5,6,7,8,9,..., ω}

But as you keep trying to understand larger and larger countable ordinals, strange things happen.  You discover that you're fighting your own mind.

As soon as you see a systematic way to generate a sequence of larger and larger countable ordinals, you know this sequence has a limit that’s larger then all of those! And this opens the door to even larger ones….

So, this journey feels a bit like trying to outrace your car’s own shadow as you drive away from the sunset: the faster you drive, the faster it shoots ahead of you. You’ll never win.

On the other hand, you never need  to lose.  You only lose when you get tired.

And that's what I love: it becomes so obvious that the struggle to understand the infinite is a kind of mind game.  But it's a game that allows clear rules and well-defined outcomes, not a disorganized mess.

In this post:

https://johncarlosbaez.wordpress.com/2016/07/04/large-countable-ordinals-part-2/

I'll take you on a tour of countable ordinals up to the Feferman–Schütte ordinal.  Hop in and take a ride!

And if you don't know the Löwenheim–Skolem theorem, you've gotta learn about it.  It's one of the big surprises of early 20th-century logic:

https://en.wikipedia.org/wiki/L%C3%B6wenheim%E2%80%93Skolem_theorem

The pink and the hearts, by the way, are just to scare certain people.

#bigness  ___

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2016-07-05 00:35:02 (48 comments; 20 reshares; 159 +1s; )Open 

Watch Juno meet Jupiter on NASA TV!   Go here:

http://www.ustream.tv/nasahdtv

Here's the timeline - all these times are Eastern Daylight Time (GMT-4):

July 4th, 9:13 p.m. Start of transmission of single frequency “tones” that will provide updates on the spacecraft’s condition.

9:16 p.m. Juno begins turning away from the sun to position the engine in the right direction to slow the spacecraft for its arrival at Jupiter.

10:41 p.m. With the main antenna pointing away from the sun, Juno switches to a smaller antenna for sending the tones.

10:45 p.m. Juno adjusts itself to eliminate any wobbling.

10:56 p.m. Juno speeds up its spin rate from two rotations a minute to five rotations a minute, a process that takes about five minutes.

11:18 p.m.  The main engine beginsfiring!<... more »

Watch Juno meet Jupiter on NASA TV!   Go here:

http://www.ustream.tv/nasahdtv

Here's the timeline - all these times are Eastern Daylight Time (GMT-4):

July 4th, 9:13 p.m. Start of transmission of single frequency “tones” that will provide updates on the spacecraft’s condition.

9:16 p.m. Juno begins turning away from the sun to position the engine in the right direction to slow the spacecraft for its arrival at Jupiter.

10:41 p.m. With the main antenna pointing away from the sun, Juno switches to a smaller antenna for sending the tones.

10:45 p.m. Juno adjusts itself to eliminate any wobbling.

10:56 p.m. Juno speeds up its spin rate from two rotations a minute to five rotations a minute, a process that takes about five minutes.

11:18 p.m.  The main engine begins firing!

11:38 p.m. The spacecraft has slowed down enough to be captured into orbit around Jupiter.

11:53 p.m. The main engine shuts off, leaving Juno in the desired orbit.

11:55 p.m. The spacecraft starts slowing its spin rate back down to two revolutions per minute.

July 5th, 12:07 a.m. Juno changes direction to point its antenna back at Earth.

12:11 a.m. Juno ends the transmission of status tones and switches to its medium-gain antenna.

12:16 a.m. Juno begins transmitting detailed telemetry, although it may take 20 minutes or longer to lock into the signal.

So, the real excitement starts at 11:18 pm on July 4th if you live on the East Coast of the US.  In California this is 8:18 pm, in London it's 4:18 am on July 5th, here in Singapore it's 11:18 am on July 5th, etc.

From the New York Times:

What could possibly go wrong?

Juno blows up.  In August 1993, NASA’s instrument-packed Mars Observer spacecraft vanished. An inquiry concluded that a fuel leak caused the spacecraft to spin quickly and fall out of communication. While Juno’s setup is different, there is always a chance of an explosion with rocket fuel.

The engine doesn’t fire at all. The Japanese probe Akatsuki was all set to arrive at Venus in December 2010, but its engine didn’t fire, and Akatsuki sailed right past Venus. Last year, Akatsuki crossed paths with Venus again, and this time, using smaller thrusters, it was able to enter orbit.

It crashes into something. Jupiter does not possess the majestic rings of Saturn, but it does have a thin of ring of debris orbiting it. Juno will pass through a region that appears clear, but that does not mean it actually is. Even a dust particle could cause significant damage, as Juno will be moving at a speed of 132,000 miles per hour relative to Jupiter.

It flies too close to Jupiter and is ripped to pieces. In one of NASA’s most embarrassing failures, the Mars Climate Orbiter spacecraft, was lost in 1999 because of a mix-up between English and metric units. Climate Orbiter went far deeper into Mars’ atmosphere than planned. On its first orbit, Juno is to pass within 2,900 miles of Jupiter’s cloud tops, so a miscalculation could be catastrophic.

The computer crashes. On July 4 last year, the mission controllers of the New Horizons spacecraft that was about to fly by Pluto experienced some nervous moments when the spacecraft stopped talking to them. The computer on New Horizons crashed while trying to interpret some new commands and compressing some images it had taken, the electronic equivalent of walking while chewing gum.

The controllers put New Horizons back in working order within a few days, and the flyby occurred without a hitch. For Juno, the scientific instruments have been turned off for its arrival at Jupiter. “We turn off everything that is not necessary for making the event work,” said Dr. Levin, the project scientist. “This is very important to get right, so you don’t do anything extra.”

The intense barrage of radiation at Jupiter could knock out Juno’s computer, even though it is shielded in a titanium vault. Usually, when there is a glitch, a spacecraft goes into “safe mode” to await new instructions from Earth, but in this case, that would be too late to save Juno. The spacecraft has been programmed to automatically restart the engine to allow it to enter orbit.

“If that doesn’t go just right, we fly past Jupiter, and of course, that’s not desirable,” Dr. Bolton said.

http://www.nytimes.com/2016/07/05/science/juno-nasa-jupiter-what-to-expect.html

#astronomy  ___

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2016-07-04 03:10:41 (25 comments; 31 reshares; 134 +1s; )Open 

Driving to infinity

A long time ago, before most of you showed up on Google+, I wrote a story about infinity.  It featured a character who was recruited by the US government to fight in the War on Chaos.  His mission was to explore larger and larger infinities.  

You can see that story in my "bigness" collection - lots of posts, each one its own little chapter.

But I keep wanting to talk about infinity - it's endlessly interesting!   I keep learning more about it.  Some posts here by +Refurio Anachro re-ignited my desire to write about it, and now I have.  Here's the first of three articles:

https://johncarlosbaez.wordpress.com/2016/06/29/large-countable-ordinals-part-1/

If you read this, you'll learn about the two basic kinds of infinities discovered by Cantor: cardinals and ordinals.   Then we'llgo on a ... more »

Driving to infinity

A long time ago, before most of you showed up on Google+, I wrote a story about infinity.  It featured a character who was recruited by the US government to fight in the War on Chaos.  His mission was to explore larger and larger infinities.  

You can see that story in my "bigness" collection - lots of posts, each one its own little chapter.

But I keep wanting to talk about infinity - it's endlessly interesting!   I keep learning more about it.  Some posts here by +Refurio Anachro re-ignited my desire to write about it, and now I have.  Here's the first of three articles:

https://johncarlosbaez.wordpress.com/2016/06/29/large-countable-ordinals-part-1/

If you read this, you'll learn about the two basic kinds of infinities discovered by Cantor: cardinals and ordinals.   Then we'll go on a road trip through larger and larger ordinals.

The picture here shows some of the first ones we'll meet on our trip.  Omega, written ω, is the first infinite ordinal:

ω = {0,1,2,3,4,5,6,7,8,9,...}

Each turn of the spiral here takes you to a higher power of omega, and if you go around infinitely many times, you reach omega to the omegath power.   There are many ways to visualize this ordinal, and I explain a few. 

But my road trip will take you much further than that!

In this first episode, we reach an ordinal called epsilon nought, first discovered by Cantor.  In the second episode we'll go up the Feferman–Schütte ordinal.  In the third we'll reach the small Veblen ordinal and even catch a glimpse of the large Veblen ordinal.

All these are countable ordinals, and you can write computer programs to calculate with them, so I consider them just as concrete as the square root of 2.  And yet, they're quite mind-blowing.

#bigness  ___

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2016-07-03 08:00:09 (23 comments; 9 reshares; 64 +1s; )Open 

Scary geometry

This is a view of Barth's decic surface drawn by +Abdelaziz Nait Merzouk.  It's a frightening shape with 345 cone-shaped singularities - the most possible for a surface described by a polynomial of degree 10. 

And yet, despite its nightmarish complexity, this surface is highly symmetrical.  It has the same symmetries as a regular icosahedron!    

For more views of this surface, go here:

http://blogs.ams.org/visualinsight/2016/07/01/barth-decic/

I have no idea how Wolf Barth dreamt up this surface, along with the closely related 'Barth sextic', back in 1994.   The equations describing them feature the golden ratio... but they're complicated.  I bet there's a more conceptual way to get your hands on these surfaces.  If you know it, please tell me!

#geometry  

Scary geometry

This is a view of Barth's decic surface drawn by +Abdelaziz Nait Merzouk.  It's a frightening shape with 345 cone-shaped singularities - the most possible for a surface described by a polynomial of degree 10. 

And yet, despite its nightmarish complexity, this surface is highly symmetrical.  It has the same symmetries as a regular icosahedron!    

For more views of this surface, go here:

http://blogs.ams.org/visualinsight/2016/07/01/barth-decic/

I have no idea how Wolf Barth dreamt up this surface, along with the closely related 'Barth sextic', back in 1994.   The equations describing them feature the golden ratio... but they're complicated.  I bet there's a more conceptual way to get your hands on these surfaces.  If you know it, please tell me!

#geometry  ___

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2016-07-02 00:20:03 (25 comments; 32 reshares; 120 +1s; )Open 

Jupiter orbit insertion

On the 4th of July, a NASA spacecraft named Juno will try to start orbiting Jupiter.  It has traveled for 5 years and 2.8 billion kilometers to get there.  This is going to be exciting!

Juno will try to aim its main engine towards the Sun, turn it on for 35 minutes, and slow down to 58 kilometers per second, so it can be captured by Jupiter's gravitational field.   Says the lead scientist:

“There’s a mixture of tension and anxiety because this is such a critical maneuver and everything is riding on it. We have to get into orbit. The rocket motor has to burn at the right time, in the right direction, for just the right amount of time.”

With luck, Juno will enter a highly eccentric polar orbit, and make 37 orbits lasting 14 days each.   Each time it will dive down to just 4000 kilometers above Jupiter'scloud tops... more »

Jupiter orbit insertion

On the 4th of July, a NASA spacecraft named Juno will try to start orbiting Jupiter.  It has traveled for 5 years and 2.8 billion kilometers to get there.  This is going to be exciting!

Juno will try to aim its main engine towards the Sun, turn it on for 35 minutes, and slow down to 58 kilometers per second, so it can be captured by Jupiter's gravitational field.   Says the lead scientist:

“There’s a mixture of tension and anxiety because this is such a critical maneuver and everything is riding on it. We have to get into orbit. The rocket motor has to burn at the right time, in the right direction, for just the right amount of time.”

With luck, Juno will enter a highly eccentric polar orbit, and make 37 orbits lasting 14 days each.   Each time it will dive down to just 4000 kilometers above Jupiter's cloud tops, closer than we've ever come!  Each time it will shoot back up to a height of 2.7 million kilometers.   It will map Jupiter using many instruments.  The first dive is scheduled for August.

Juno will gradually be damaged by Jupiter's intense radiation, even though the main computer is encased in a 200-kilogram titanium box.   After its last orbit, it will deliberately plunge to its death - so that it has no chance of contaminating the oceans of Europa.

Juno has already entered Jupiter's magnetosphere - the region of space dominated by Jupiter's powerful magnetic field.  You can hear it here:

http://www.cnet.com/news/the-sounds-of-juno-approaching-jupiter-are-totally-spooky/

For details of Juno's trajectory, go here:

http://spaceflight101.com/juno/juno-mission-trajectory-design/

And watch the NASA "preview" here.  It's like the preview of a science fiction movie, emphasizing the dangers rather than the potential rewards - but it's fun.

The Jupiter orbit insertion should begin at 03:18 July 5th UTC, which is 20:18 on the 4th of July in California.

#astronomy  ___

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2016-06-30 04:59:55 (29 comments; 20 reshares; 84 +1s; )Open 

Zero to the zero

What's zero to the zeroth power?  People love to argue about this question.   Wimps - that is, wisely cautious people - say that it's undefined. Bolder people take bolder views.  +David Tanzer has written a nice article about this puzzle:

https://johncarlosbaez.wordpress.com/2016/06/25/a-quirky-function/

and various readers, including the redoubtable Greg Egan, have posted beautiful animations in the comments. 

The animation here was made by one of those wonderful pseudonymous internet beings - in this case, someone named "etatoby".  It's a graph of the surface

z = x ʸ

in the uncontroversial region, namely where x > 0.   The horizontal arrows point along the x and y axes, forming the boundary of the first quadrant: the region where x > 0 and y > 0.  

If you lookcarefull... more »

Zero to the zero

What's zero to the zeroth power?  People love to argue about this question.   Wimps - that is, wisely cautious people - say that it's undefined. Bolder people take bolder views.  +David Tanzer has written a nice article about this puzzle:

https://johncarlosbaez.wordpress.com/2016/06/25/a-quirky-function/

and various readers, including the redoubtable Greg Egan, have posted beautiful animations in the comments. 

The animation here was made by one of those wonderful pseudonymous internet beings - in this case, someone named "etatoby".  It's a graph of the surface

z = x ʸ

in the uncontroversial region, namely where x > 0.   The horizontal arrows point along the x and y axes, forming the boundary of the first quadrant: the region where x > 0 and y > 0.  

If you look carefully, you can see that x ʸ = 0 when x = 0 and y > 0. 

And if you look harder, you can see that x ʸ takes a constant positive value when x > 0 and y = 0.  This is consistent with the fact that x ⁰ = 1 in this case.

But the really interesting part is that x ʸ approaches all possible positive values as x and y both get close to zero.  This is the main reason that cautious people say 0 ⁰ is undefined.

Puzzle: when we say someone is "redoubtable", we don't mean that you can doubt them again.  We mean they're formidable or awe-inspiring.  So what's the etymology of this word?

Googling is cheating. ___

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2016-06-28 22:42:52 (29 comments; 26 reshares; 100 +1s; )Open 

Metaculus - a prediction website

Metaculus is a website where you can ask about future events and predict their probabilities.  The "wisdom of crowds" says that this is a pretty reasonable way to divine the future.  But some people are better predictors than others, and this skill can be learned.  Check it out:

http://www.metaculus.com/questions/

Metaculus was set up by two professors at U.C. Santa Cruz.  Anthony Aguirre, a physicist, is a co-founder of the Foundational Questions Institute, which tries to catalyze breakthrough research in fundamental physics, and the Future of Life Institute, which studies disruptive technologies like AI.  Greg Laughlin, an astrophysicist, is an expert at predictions from the millisecond predictions relevant to high-frequency trading to the ultra-long-term stability of the solar system.

I've askedand ... more »

Metaculus - a prediction website

Metaculus is a website where you can ask about future events and predict their probabilities.  The "wisdom of crowds" says that this is a pretty reasonable way to divine the future.  But some people are better predictors than others, and this skill can be learned.  Check it out:

http://www.metaculus.com/questions/

Metaculus was set up by two professors at U.C. Santa Cruz.  Anthony Aguirre, a physicist, is a co-founder of the Foundational Questions Institute, which tries to catalyze breakthrough research in fundamental physics, and the Future of Life Institute, which studies disruptive technologies like AI.  Greg Laughlin, an astrophysicist, is an expert at predictions from the millisecond predictions relevant to high-frequency trading to the ultra-long-term stability of the solar system.

I've asked and answered a few questions there.  It's fun, and it will get more fun as more people take it seriously!   Here's some stuff from their latest report:

Dear Metaculus Users,

We recently logged our 10,000th prediction. Not quite Big Data (which will take lots more growth), but we’re making progress! With this milestone passed, it seems like a good time to share an overview of our results
.
First, the big picture. This can be summarized with a single histogram that shows the distribution of the first 10,042 predictions on our first 146 questions. Unambiguously, the three most popular predictions are 1%, 50% and 99%, with spikes of varying strength at each multiple of 5%. There’s a definite overall skew toward lower percentages. This phenomenon stems in part from the fact that the subset of provocative low-probability questions is most naturally worded in a way that the default outcome is negative, e.g., Question: Will we confirm evidence for megastructures orbiting the star KIC 8462852? (Answer: No.) The histogram also makes the point that while 99% confidence — the equivalent of complete confidence -- is very common, it’s very rare that anyone is ever 98% sure about anything. One takeaway from the pileup at 1% and 99% is that we could use more possible values there, so we plan to introduce an expanded range, from 0.1% to 99.9% soon — but as cautioned below, be careful in using it. Excluding the 1% and 99% spikes and smoothing a bit, the prediction distribution turns out to be a pretty nice gaussian, illustrating the ubiquitous effect of the law of large numbers.

The wheels of Metaculus are grinding slowly, but they grind very fine. Almost 80% of the questions that have been posed on site are still either active (open), or closed (pending resolution) We are starting, however, to get meaningful statistics on questions that have resolved to date — a collection that spans a wide range of topics (from Alpha Go to LIGO and from VIX to SpaceX). We’ve been looking at different metrics to evaluate collective predictive success. A simple approach is to chart the fraction of outcomes that actually occurred, after aggregating over all of the predictions in each percentage bin. In the limit of a very large number of optimally calibrated predictions on a very large number of questions, the result would be the straight line shown in gold on Figure 2 below. It’s clear that the optimal result compares quite well to the aggregation produced by the Metaculus user base. Error bars are 25% and 75% confidence intervals, based on bootstrap resampling of the questions. The only marginally significant departure from the optimal result comes at the low end: as a whole, the user base has been slightly biased toward pessimism, assigning a modest overabundance of low probabilities to events that actually wound up happening. In particular, the big spike in the 1% bin in Figure 1 isn’t fully warranted. (This is also somewhat true at 99%: these predictions have come true 90% of the time.) Take-away: if you’re inclined to pull the slider all the way to the left or even right, give it a second thought...

It has been demonstrated that the art of successful prediction is a skill that can be learned. Predictors get better over time, and so it’s interesting to look at the performance of the top predictors on Metaculus, as defined by users with a current score greater than 500. The histogram of predictions for the subset of top users shows some subtle differences with the histogram of all the predictions. The top predictors tend to be more equivocal. The 50% bin is still highly prominent, whereas the popularity of 1% votes is quite strongly diminished.

I recently predicted - not on Metaculus - that Hillary Clinton has a 99% chance of getting the Democratic nomination.  Maybe I should have said 98%.  But I definitely should put my prediction on Metaculus!  This could develop into a useful resource.

If you want to become a "super-forecaster", you need to learn about the Good Judgment Project.  Start here:

http://www.npr.org/sections/parallels/2014/04/02/297839429/-so-you-think-youre-smarter-than-a-cia-agent

A little taste:

For the past three years, Rich and 3,000 other average people have been quietly making probability estimates about everything from Venezuelan gas subsidies to North Korean politics as part of the Good Judgment Project, an experiment put together by three well-known psychologists and some people inside the intelligence community.

According to one report, the predictions made by the Good Judgment Project are often better even than intelligence analysts with access to classified information, and many of the people involved in the project have been astonished by its success at making accurate predictions.

Then read Philip Tetlock's books Expert Political Judgment and Superforecasting: The Art and Science of Prediction.  I haven't!   But I would like to become a super-forecaster.___

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2016-06-27 15:44:24 (20 comments; 25 reshares; 144 +1s; )Open 

Why bees are fuzzy

The fuzz on bees helps them collect pollen.  But it may also help them detect electric fields!

The surprising part - to me - is that flowers have electric fields.   And different kinds of flowers have noticeably different fields.

Gregory Sutton, a  biomechanical engineer who is studying this, says that flower petals tend to accumulate electric charge.  So, they produce an electric field just like when you rub a balloon on a woolly sweater - but smaller:

“It’s a very small electrical field, which is why we're quite astounded that bees can actually detect it,” Sutton says. “And there is different charge distribution at different locations on the petals of different species of flowers. So two flowers of the same species will have a similar electric field, whereas two flowers of a different species will have differentelectric fi... more »

Why bees are fuzzy

The fuzz on bees helps them collect pollen.  But it may also help them detect electric fields!

The surprising part - to me - is that flowers have electric fields.   And different kinds of flowers have noticeably different fields.

Gregory Sutton, a  biomechanical engineer who is studying this, says that flower petals tend to accumulate electric charge.  So, they produce an electric field just like when you rub a balloon on a woolly sweater - but smaller:

“It’s a very small electrical field, which is why we're quite astounded that bees can actually detect it,” Sutton says. “And there is different charge distribution at different locations on the petals of different species of flowers. So two flowers of the same species will have a similar electric field, whereas two flowers of a different species will have different electric fields.”

Together with biophysics researcher Erica Morley and some other scientists, Sutton did experiments to test the theory that bees use electric fields to help find food.  

They built 10 flowers with the same shape, size and smell. They put sugar water on some of the flowers and then added small static electric fields to those flowers. On the rest of the flowers, they put bitter water and no electric field. They let the bees loose among the flowers and kept moving the flowers around so the bees couldn’t learn the location of the sugar water.
 
“As they forage, they start to go to the flowers with the sugar water 80 percent of the time,” Sutton says. “So you know they've figured out the difference between the two sets of flowers. The last step is you just turn off the voltage and then check to see if they can continue telling the difference. And when we turned off the voltage, they were unable to tell the difference. And that's how we knew it was the voltage itself that they were using to tell the difference between the flowers.”

It's good that they did this last step, because otherwise I'd be unconvinced.  They also studied the mechanism that bees use to detect electric fields.  Basically, bee hairs get pulled by an electric field, and the bee can feel it:

“What we found in bees is that they're using a mechanic receptor,” Morley says. “It's not a direct coupling of this electrical signal to the sensory system. They’re using mechanical movement of hair in a very non-conductive medium. Air doesn't conduct electricity very well — it's very resistive. So these hairs have moved in response to the field, which then causes the nerve impulses from the cells at the bottom of the hair.”

I love results like this, which show the world is bigger and more interesting than I thought.   But I'm a bit suspicious too, so I hope more scientists try to replicate these experiments or poke holes in them.

The paper is open-access, so if you have questions you can read it yourself!

• Gregory P. Sutton, Dominic Clarke, Erica L. Morley and Daniel Robert, Mechanosensory hairs in bumblebees (Bombus terrestris) detect weak electric fields, Proc. Nat. Acad. Sci. 113 (2016), 7261–7265. http://www.pnas.org/content/early/2016/05/25/1601624113.full

I got my quotes from here:

http://www.pri.org/stories/2016-06-26/flowers-give-electrical-signals-bees

#spnetnwork   #bees #mechanosensory  ___

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2016-06-24 16:58:40 (85 comments; 4 reshares; 105 +1s; )Open 

Youth

A lynx kitten bounds forward, confident and focused.

I need this picture today, to cheer myself up.  I don't like the Brexit.  The very best possible interpretation I can put on it is that it's ordinary folks poking a stick in the eye of the elite, demanding more local control of government, more democracy.   Maybe the elite will wake up, stop trying to hog all the wealth, and realize that in the long run it pays to help the downtrodden.  

Maybe London will become less dominated by corrupt financiers.   Maybe Scotland will become independent and join the EU.   

I can imagine a wave of decentralization and localization being a good thing.... if  it's balanced by the right larger-scale structures, allowing plenty of free trade, free movement of people, and so on.   But I don't get any sense that the Brexiters have aconstructiv... more »

Youth

A lynx kitten bounds forward, confident and focused.

I need this picture today, to cheer myself up.  I don't like the Brexit.  The very best possible interpretation I can put on it is that it's ordinary folks poking a stick in the eye of the elite, demanding more local control of government, more democracy.   Maybe the elite will wake up, stop trying to hog all the wealth, and realize that in the long run it pays to help the downtrodden.  

Maybe London will become less dominated by corrupt financiers.   Maybe Scotland will become independent and join the EU.   

I can imagine a wave of decentralization and localization being a good thing.... if  it's balanced by the right larger-scale structures, allowing plenty of free trade, free movement of people, and so on.   But I don't get any sense that the Brexiters have a constructive vision for the future. 

Back to the theme of youth:

The young are generally bolder, less careful, less fearful.  It's got pros and cons.

75% of British people between ages 18 and 24 said they voted for Britain to stay in the EU.   For people 25-49 it was 56%.  For people 50-64 it was 44%.  For people above 65, just 39%.

So this is an interesting case.  Perhaps the old are more fearful - of refugees, of Polish plumbers, of EU bureaucrats - but in this case they were more eager to do something rash.   It's quite amazing how little is known about what will happen next!    About all we be sure about is that it will create a big mess.

Good luck, Britain!  Good luck, EU!___

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2016-06-23 15:33:57 (22 comments; 11 reshares; 77 +1s; )Open 

Superstar

This is the small stellated dodecahedron.   It's like a star made of stars.   It has 12 pentagrams, 5-pointed stars, as faces.  These stars cross over each other.  Five meet at each sharp corner.

But here's the really cool part: you should think of each pentagram as a pentagon that's been mapped into space in a very distorted way, with a 'branch point of order 2' at its center.

What does that mean?  

Stand at the center of a pentagon!   Measure the angle you see between two corners that are connected by an edge.  You'll get 2π/5.   But now stand at the center of a pentagram.   Measure the angle you see between two corners that are connected by an edge.  You get 4π/5.  Twice as big! 

So, to map a pentagon into space in a way that makes it look like a pentagram, you need to wrap ittwice around it... more »

Superstar

This is the small stellated dodecahedron.   It's like a star made of stars.   It has 12 pentagrams, 5-pointed stars, as faces.  These stars cross over each other.  Five meet at each sharp corner.

But here's the really cool part: you should think of each pentagram as a pentagon that's been mapped into space in a very distorted way, with a 'branch point of order 2' at its center.

What does that mean?  

Stand at the center of a pentagon!   Measure the angle you see between two corners that are connected by an edge.  You'll get 2π/5.   But now stand at the center of a pentagram.   Measure the angle you see between two corners that are connected by an edge.  You get 4π/5.  Twice as big! 

So, to map a pentagon into space in a way that makes it look like a pentagram, you need to wrap it twice around its central point.   That's what a branch point of order 2 is all about.

That's the cool way to think of this shape you see spinning before you.  It's a surface made of 12 pentagons, each wrapped twice around its center, with 5 meeting at each sharp corner. 

There's another way to think about this surface!   Any equation of this sort

z⁵ + pz + q = 0

has 5 solutions, or roots.   To make this true we need to bend the rules a bit.  First, we let the solutions be complex numbers...  so let p and q be complex too.  Second, we must allow for the possibility of repeated roots: when you factor z⁵ + pz + q, the same root may show up twice.

Now here's the cool part: the small stellated dodecahedron is the set of all lists of 5 numbers that are roots of some equation of this form:

z⁵+ pz + q = 0

So it's not just a pretty star-shaped thing.  It's a serious mathematical entity!    It's actually a Riemann surface, the most symmetrical Riemann surface with 4 holes!   You can build it starting from a tiling of the hyperbolic plane by pentagons.  In this tiling 5 pentagons meet at each corner - just like 4 squares meet at each corner in a square tiling of the ordinary plane.

It's all about the number 5, which has a lot of star power.  To understand more, read my blog article:

http://blogs.ams.org/visualinsight/2016/06/15/small-stellated-dodecahedron/

Most of this was discovered by Felix Klein in 1877.   He discovered lots of cool facts like this.  It's almost annoying.  I keep learning cool things about Riemann surfaces and the hyperbolic plane... and it keeps turning out they were discovered by Klein.    He found more than his fair share. 

By the way, this post and many others are now part of my "geometry" collection.   If you want to binge on beauty, go there now:

https://plus.google.com/collection/UIQgaB

But beware: next morning you may wake up in a gutter with a headache, seeing stars.

This image was created by someone named 'Cyp' and placed on Wikicommons.

#geometry  ___

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2016-06-21 17:38:01 (0 comments; 24 reshares; 117 +1s; )Open 

Broke — but self-funding

During the primaries, Trump claimed he was rich and couldn't be bought.  He said he wouldn't have a super-PAC.   Now he has a lot of super-PACs - all fighting each other.   But his campaign has very little cash!  

In May he tweeted:

Good news is that my campaign has perhaps more cash than any campaign in the history of politics.

But this was a lie.   By the end of May his campaign had less than $1.3 million.  At least, that's what he reported to the Federal Election Commission.  

That may sound like a lot if you don't know US politics.  But Clinton, by comparison, had $42 million.   Even Ben Carson - remember that guy, the nutty candidate who claimed the pyramids were built for storing grain? - had $1.7 million when he quit back in March.

So, by US standards, Trump'scampaign is brok... more »

Broke — but self-funding

During the primaries, Trump claimed he was rich and couldn't be bought.  He said he wouldn't have a super-PAC.   Now he has a lot of super-PACs - all fighting each other.   But his campaign has very little cash!  

In May he tweeted:

Good news is that my campaign has perhaps more cash than any campaign in the history of politics.

But this was a lie.   By the end of May his campaign had less than $1.3 million.  At least, that's what he reported to the Federal Election Commission.  

That may sound like a lot if you don't know US politics.  But Clinton, by comparison, had $42 million.   Even Ben Carson - remember that guy, the nutty candidate who claimed the pyramids were built for storing grain? - had $1.7 million when he quit back in March.

So, by US standards, Trump's campaign is broke.  

And he keeps putting campaign money back into his own pocket!

Throughout his campaign, up to the end of May, he has given $6.2 million of campaign funds to companies he owns.  That's roughly 10% of his campaign spending so far.    And in May this rose to almost 20%: he spent $6.7 million on his campaign, but over $1 million of that went to his own companies.

According to the Huffington Post:

The most striking expenditure in the new filings was $423,372, paid by the Trump campaign for rentals and catering at Trump’s 126-room Palm Beach, Florida, mansion, Mar-A-Lago, which Trump operates as a private club.

Other Trump-owned recipients of campaign funds include Trump Restaurants, which raked in $125,080 in rent and utilities; Trump Tower Commercial, which charged $72,800 in rent and utilities in the building that houses Trump’s campaign headquarters; the Trump National Golf Club, in Jupiter, Florida, which collected $35,845 for facilities rental and catering; and the Trump International Golf Club in West Palm Beach, Florida, which billed the campaign for $29,715, for facilities rentals and catering.

So, Trump has given a whole new meaning to the term "self-funding".  In 2000, he said:

It's very possible that I could be the first presidential candidate to run and make money on it.

It seems that Trump plans to let the Republican National Committee pay for most of his campaign.  They've got some money: they started June with $20 million in cash.  But four years ago at this time, they had more than $60 million.  Their big donors are shying away from Trump.
 
I would love to get money out of US politics.  I hadn't expected Trump to take the lead. 

Here is his May report to the Federal Election Commission:

http://docquery.fec.gov/cgi-bin/forms/C00580100/1079423/

Here is the Huffington Post article:

http://www.huffingtonpost.com/entry/trump-campaign-payments_us_5768a69ee4b0853f8bf1fe2d

Here is an article on Trump's super-PACs:

http://www.motherjones.com/politics/2016/05/donald-trump-super-pac-problem

Trump's boast that his might be the first presidential campaign to make
money:

http://www.theatlantic.com/politics/archive/2016/05/trumps-self-funding-lie/482691/

More figures from here:

http://www.wsj.com/articles/hillary-clintons-war-chest-grows-aided-by-super-pac-1466464804

http://www.msnbc.com/rachel-maddow-show/more-ways-one-the-trump-campaign-broke___

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2016-06-11 17:54:44 (17 comments; 24 reshares; 167 +1s; )Open 

Big stick insect

One of the world's largest insects lives in Australia.   It looks like a stick and it's called Ctenomorpha gargantua.   It's very hard to find, because it lives in the highest parts of the rainforests in Queensland, and it's only active at night! 

In 2014 one fell down and was found hanging on a bush.   Scientists took it to the Museum Victoria, in Melbourne.  They named it Lady Gaga-ntuan.   Now it has a daughter that's 0.56 meters long - that is, 22.2 inches long.  

https://en.wikipedia.org/wiki/Ctenomorpha_gargantua

#biology

Big stick insect

One of the world's largest insects lives in Australia.   It looks like a stick and it's called Ctenomorpha gargantua.   It's very hard to find, because it lives in the highest parts of the rainforests in Queensland, and it's only active at night! 

In 2014 one fell down and was found hanging on a bush.   Scientists took it to the Museum Victoria, in Melbourne.  They named it Lady Gaga-ntuan.   Now it has a daughter that's 0.56 meters long - that is, 22.2 inches long.  

https://en.wikipedia.org/wiki/Ctenomorpha_gargantua

#biology___

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2016-06-09 15:42:47 (46 comments; 5 reshares; 50 +1s; )Open 

Silly sounding elements

Forget Trump. We have until November to prevent scientists from naming an element oganesson

I don't have anything against Yuri Oganessian, a pioneer in the study of  highly radioactive, short-lived elements.   I just think the word "oganesson" stumbles off the tongue like a dazed, jet-lagged passenger staggering off a plane and falling down the stairway. 

And it's a noble gas!   A noble gas should sound noble.  

Neon.  Argon.  Krypton.  Xenon.  Oganesson.  

Which one does not belong?  Which name was created by somebody without a shred of poetry in their soul?

The International Union of Pure and Applied Chemistry, or IUPAC, has begun a five-month public review, ending 8 November 2016, before it names these elements:

Element 113: Nihonium (Nh)
Element 115,Moscovium (Mc)... more »

Silly sounding elements

Forget Trump. We have until November to prevent scientists from naming an element oganesson

I don't have anything against Yuri Oganessian, a pioneer in the study of  highly radioactive, short-lived elements.   I just think the word "oganesson" stumbles off the tongue like a dazed, jet-lagged passenger staggering off a plane and falling down the stairway. 

And it's a noble gas!   A noble gas should sound noble.  

Neon.  Argon.  Krypton.  Xenon.  Oganesson.  

Which one does not belong?  Which name was created by somebody without a shred of poetry in their soul?

The International Union of Pure and Applied Chemistry, or IUPAC, has begun a five-month public review, ending 8 November 2016, before it names these elements:

Element 113: Nihonium (Nh)
Element 115, Moscovium (Mc)
Element 117, Tennessine (Ts)
Element 118, Oganesson (Og)

I have no opinions except about how the names sound and look.  Nihonium and Moscovium sound okay to me.   The word "Tennessine" is awkward.   I like the state of Tennessee.  I have nothing against it having its own highly radioactive element.   I just don't like this word.  This element is a halogen, and again it's the least pretty of the bunch:

Fluorine.  Chlorine.   Bromine.   Iodine.   Astatine.   Tennessine.

But "oganesson" is worse.  IUPAC could have done better hiring that unemployed guy who used to make up names for elements on Star Trek.  The only good thing about "oganesson" is that it has such a short half-life that we'll hardly ever need to say that word. 

I would gladly accept tennessine if it would stop "oganesson" from lurching onto the periodic table.  In fact, I'd volunteer to eat the world's entire supply of tennessine.

If you agree with me, or have other opinions, write a polite letter to Dr. Lynn M. Soby, the Executive Director of IUPAC, at

secretariat@iupac.org

PS - yes, I know helium is also a noble gas.  People gave it a name suitable for a metal, not a noble gas, before they knew better.  It's too late to call it helion.___

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2016-06-07 16:57:41 (52 comments; 42 reshares; 133 +1s; )Open 

Does dark matter have dark hair?

By now there's a lot of evidence that dark matter exists, but not so much about what it is.  The most popular theories say it's some kind of particles that don't interact much with ordinary matter, except through gravity.  These particles would need to be fairly massive - as elementary particles go - so that despite having been hot and energetic shortly after the Big  Bang, they'd move slow enough to bunch up thanks to gravity.  Indeed, the bunching up of dark matter seems necessary to explain the formation of the visible galaxies!  

Searches for dark matter particles have not found much.  The DAMA experiment, a kilometer underground in Italy, seemed to detect them.  Even better, it saw more of them in the summer, when the Earth is moving faster relative to the Milky Way, than in the winter.  That's just what you'dexpect!... more »

Does dark matter have dark hair?

By now there's a lot of evidence that dark matter exists, but not so much about what it is.  The most popular theories say it's some kind of particles that don't interact much with ordinary matter, except through gravity.  These particles would need to be fairly massive - as elementary particles go - so that despite having been hot and energetic shortly after the Big  Bang, they'd move slow enough to bunch up thanks to gravity.  Indeed, the bunching up of dark matter seems necessary to explain the formation of the visible galaxies!  

Searches for dark matter particles have not found much.  The DAMA experiment, a kilometer underground in Italy, seemed to detect them.  Even better, it saw more of them in the summer, when the Earth is moving faster relative to the Milky Way, than in the winter.  That's just what you'd expect!  But other similar experiments haven't seen anything.  So most physicists doubt the DAMA results.  

Maybe dark matter is not made of massive weakly interacting particles.  Maybe it's a superfluid made of light but strongly interacting particles.  Maybe there are lot more 25-solar-mass black holes than most people think!  There are lots of theories, and I don't have time to talk about them all.  

I just want to tell you about a cool idea which assumes that dark matter is made of massive weakly interacting particles.  It's still the most popular theory, so we should take it seriously and ask: if they exist, what would these particles do?

In the early Universe they'd attract each other by gravity.  They'd bunch up, helping seed the formation of galaxies.  But after stars and planets formed, they'd pull at the dark matter, making it thicker in some places, thinner in others.  

And this is something we can simulate using computers!  After all, the relevant physics is well-understood: just Newton's law of gravity, applied to stars, planets and zillions of tiny dark matter particles.  

Gary Prezeau of NASA's Jet Propulsion Laboratory did these simulations and discovered something amazing. 

When dark matter flows past the Earth, it gets deflected and focused by the Earth's gravity.  Like light passing through a lens, it gets intensely concentrated at certain locations!

This creates long thin 'hairs' where the density of dark matter is enhanced by a factor of 10 million.   Each hair is densest at its 'root'.   At the root, the density of dark matter is about a billion times greater than average!

The hairs in this picture are not to scale: the Earth is drawn too big.   The roots of the hairs would be about a million kilometers from Earth, while the Earth's radius is only 6,400 kilometers.  

Of course we don't know dark matter particles exist.  What's cool is that if they exist, it forms such beautiful structures!  And if we could do a dark matter search in space, near one of these possible roots, we might have a better chance of finding something.   

Let me paraphrase Prezeau, because the real beauty is in the details.  From his abstract:

It is shown that compact bodies form strands of concentrated dark matter filaments henceforth simply called 'hairs'. These hairs are a consequence of the fine-grained stream structure of dark matter halos surrounding galaxies, and as such they constitute a new physical prediction of the standard model of cosmology. Using both an analytical model of planetary density and numerical simulations (a fast way of computing geodesics) with realistic planetary density inputs, dark matter streams moving through a compact body are shown to produce hugely magnified dark matter densities along the stream velocity axis going through the center of the body. Typical hair density enhancements are 10^7 for Earth and 10^8 for Jupiter. The largest enhancements occur for particles streaming through the core of the body that mostly focus at a single point called the root of the hair. For the Earth, the root is located at about 10^6 kilometers from the planetary center with a density enhancement of around 10^9 while for a gas giant like Jupiter, the root is located at around 10^5 kilometes with a enhancement of around 10^11. Beyond the root, the hair density precisely reflects the density layers of the body providing a direct probe of planetary interiors.

The mathematicians and physicists among you may enjoy even more detail.  Again, I'll paraphrase:

According to the standard model of cosmology, the velocity dispersion of cold dark matter (CDM) is expected to be greatly suppressed as the universe expands and the CDM collisionless gas cools.  In particular, for a weakly interacting mass particle with mass of 100 GeV that decoupled from normal matter when the Universe cooled to an energy of 10 MeV per particle, the velocity dispersion is only about 0.0003 meters per second.

As the Universe cools and the nonlinear effects of gravity become more prominent and galactic halos grow, the dispersion of velocities will increase somewhat, but 10 kilometers per second is an upper limit on the velocity dispersion of the resulting dark matter streams.

Dark matter starts out having a very low spread in velocities, but its location can be anywhere.  So, it forms a 3-dimensional sheet in the 6-dimensional space of position-velocity pairs, called phase space

As time passes this sheets gets bent, but it can never be broken.   When this sheet gets folded enough, we get a 'caustic where lots of different dark matter particles have almost the same position, though different velocities.  You can see a caustic by shining light into a reflective coffee cup, or shining light through a magnifying glass.  The same math applies here:

A phase-space perspective sheds additional light on the processes affecting the CDM under the influence of gravity.  When the CDM decouples from normal matter, the CDM occupies a 3-dimensional sheet in the 6-dimensional phase space since it has a tiny velocity dispersions. The process of galactic halo formation cannot tear this hypersurface, thanks to generalization of Liouville’s theorem.  Under the influence of gravity, a particular phase space volume of the hypersurface is stretched and folded with each orbit of the CDM creating layers of fine-grained dark matter streams, each with a vanishingly small velocity dispersion. These stretches and folds also produce caustics: regions with very high CDM densities that are inversely proportional to the square root of the velocity dispersion.

Here are some more pictures:

http://www.nasa.gov/feature/jpl/earth-might-have-hairy-dark-matter

and here's the paper:

• Gary Prezeau, Dense dark matter hairs spreading out from Earth, Jupiter and other compact bodies, http://arxiv.org/abs/1507.07009.

#spnetwork arXiv:1507.07009 #astronomy  ___

posted image

2016-06-04 16:57:18 (0 comments; 59 reshares; 204 +1s; )Open 

Thin-skinned

By now you've probably heard: Trump said he'd given $1 million of his own money to veterans groups, but he actually hadn't.   His campaign manager, too, falsely claimed he had given this money. 

4 months later, the Washington Post and other papers started investigating.  They contacted Trump and asked what was up.  On May 24th, feeling the heat, he broke down and handed over the million bucks.

Other donors had also given money to the Donald J. Trump Foundation on the promise that Trump would then give it to veterans.  And he did - after  he was caught.  The Associated Press found that many of his checks were dated May 24, after  the Washington Post story came out.

That's bad enough, but the really interesting part is the temper tantrum that Trump threw at a press conference where he publicly announced that he'dfinally ... more »

Thin-skinned

By now you've probably heard: Trump said he'd given $1 million of his own money to veterans groups, but he actually hadn't.   His campaign manager, too, falsely claimed he had given this money. 

4 months later, the Washington Post and other papers started investigating.  They contacted Trump and asked what was up.  On May 24th, feeling the heat, he broke down and handed over the million bucks.

Other donors had also given money to the Donald J. Trump Foundation on the promise that Trump would then give it to veterans.  And he did - after  he was caught.  The Associated Press found that many of his checks were dated May 24, after  the Washington Post story came out.

That's bad enough, but the really interesting part is the temper tantrum that Trump threw at a press conference where he publicly announced that he'd finally given the promised money.

He blasted the media for making him “look bad” by insisting that he account for $6 million.  He called them "dishonest" and "not good people", without giving any example of dishonesty.  And he personally attacked ABC reporter Tom Llamas.

“I’m not looking for credit,” Trump insisted, contrary to all appearances. “But what I don’t want is when I raise millions of dollars have people say — like this sleazy guy over here from ABC. He’s a sleaze in my book.”

"Why am I a sleaze?" Llamas shot back.

“You’re a sleaze!” Trump shouted. “Because you know the facts and you know the facts well.”   Llamas, you see, had just asked a question about this issue.  He also had a history of asking Trump tough questions about his anti-immigrant rhetoric. 

It's shocking for a US presidential candidate to act this way.  This is what a Chicago gangster or tinpot dictator would do.

“Is this what it’s going to be like covering you if you’re president?” one reporter asked.

Trump’s reply: “Yeah, it is. I’m going to continue to attack the press.”

And indeed, Trump has said that if he becomes president, he will "open up" the libel laws to make it easier to sue people who say things he doesn't like.  This is exactly  what dictators do.

In 2005, Timothy O'Brien wrote a book TrumpNation: The Art Of Being The Donald.   He raised questions about Trump's claims of vast wealth.  Trump promptly sued O'Brien for $5 billion.  It was the largest libel lawsuit in U.S. history.  Maybe Trump was trying to gain the wealth he didn't actually have.   But the lawsuit was dismissed, because of course it's not libel to report that someone is not as rich as they claim.

It's tough to take public criticism.  Hillary Clinton knows this well.   But Clinton is not thin-skinned like Trump.   I don't want a president who throws hissy fits at press conferences, yells at reporters, and threatens writers with lawsuits.

The Washington Post article about Trump on May 24:

https://www.washingtonpost.com/news/post-politics/wp/2016/05/24/four-months-later-donald-trump-says-he-gave-1-million-to-veterans-group/

A video of Trump's press conference:

https://www.youtube.com/watch?v=eJ5kNEL0KzI

On Trump wanting to "open up" libel laws, and suing O'Brien:

http://www.npr.org/2016/03/24/471762310/donald-trump-wants-to-open-up-libel-laws-so-he-can-sue-news-outlets___

posted image

2016-06-03 17:02:01 (19 comments; 14 reshares; 95 +1s; )Open 

A mathematical mystery - part 3

Especially before the fall of the USSR, the best Russian mathematicians would often meet and discuss their work at seminars. 

Gelfand's seminar in Moscow was especially famous, since he would stop speakers any time they said something unclear.   In fact, sometimes he'd appoint an audience member to play the role of arbiter: if this guy in the audience doesn't understand it, the speaker has to explain it better!  

As a result, the seminar would often go on until late at night, even after the building was locked up.  But everyone learned a lot of math.

With such exhaustive seminars, publishing proofs sometimes became a mere afterthought.  You'll often see short papers from this era making important claims with just a tiny sketch of an argument to back them up.

That annoyed Westernmathem... more »

A mathematical mystery - part 3

Especially before the fall of the USSR, the best Russian mathematicians would often meet and discuss their work at seminars. 

Gelfand's seminar in Moscow was especially famous, since he would stop speakers any time they said something unclear.   In fact, sometimes he'd appoint an audience member to play the role of arbiter: if this guy in the audience doesn't understand it, the speaker has to explain it better!  

As a result, the seminar would often go on until late at night, even after the building was locked up.  But everyone learned a lot of math.

With such exhaustive seminars, publishing proofs sometimes became a mere afterthought.  You'll often see short papers from this era making important claims with just a tiny sketch of an argument to back them up.

That annoyed Western mathematicians.  And I've bumped into a few mysteries that I'm having trouble with, thanks to these short Russian papers without clear proofs.  Here is one.

This image by Greg Egan shows the set of points (a,b,c) for which the quintic

x^5 + ax^4 + bx^2 + c

has repeated roots... with the plane c = 0 removed.  You'll notice this surface crosses over itself in a cool way, creating lines of sharp cusps

Vladimir Arnol'd, who ran one of these famous seminars, says that one O. V. Lyashko studied this surface in 1982 with the help of a computer - a very primitive computer by our standards, I'm sure.  And he says Lyashko proved this surface looks the same as another surface defined using the icosahedron. 

Arnol'd doesn't mention removing the plane c = 0, so his claim is technically wrong.  But if you remove that plane, it looks right!   So I'd like to see a proof that these surfaces are the same (after a smooth change of coordinates).   The icosahedron and the quintic equation are connected in many ways, so there should be a nice explanation.  But I don't know it!

For more details on this surface, see my Visual Insight  blog post:

http://blogs.ams.org/visualinsight/2016/06/01/discriminant-of-restricted-quintic/

You'll also see the other surface, defined using the icosahedron.  And you can read a full explanation of that other surface here:

http://blogs.ams.org/visualinsight/2016/05/15/discriminant-of-the-icosahedral-group/

As I explain, the same surface shows up in yet another disguise - but again, I don't know a proof!   If you make progress on these mysteries, let me know!

The icosahedron is connected to some of the most fascinating symmetrical structures in the mathematical universe, such as E8 and the Golay code.   I'm trying to get to the bottom of this, so every clue helps.

Here is a longer description of Gelfand's seminar, as told by Simon Gindikin:

The Gelfand seminar was always an important event in the very vivid mathematical life in Moscow, and, doubtless, one of its leading centers. A considerable number of the best Moscow mathematicians participated in it at one time or another. Mathematicians from other cities used all possible pretexts to visit it. I recall how a group of Leningrad students agreed to take turns to come to Moscow on Mondays (the day of the seminar, to which other events were linked), and then would retell their friends what they had heard there. There were several excellent and very popular seminars in Moscow, but nevertheless the Gelfand seminar was always an event.

I would like to point out that, on the other hand, the seminar was very important in Gelfand's own personal mathematical life. Many of us witnessed how strongly his activities were focused on the seminar. When, in the early fifties, at the peak of antisemitism, Gelfand was chased out of Moscow University, he applied all his efforts to seminar. The absence of Gelfand at the seminar, even because of illness, was always something out of the ordinary.

One cannot avoid mentioning that the general attitude to the seminar was far from unanimous. Criticism mainly concerned its style, which was rather unusual for a scientific seminar. It was a kind of a theater with a unique stage director playing the leading role in the performance and organizing the supporting cast, most of whom had the highest qualifications. I use this metaphor with the utmost seriousness, without any intention to mean that the seminar was some sort of a spectacle. Gelfand had chosen the hardest and most dangerous genre: to demonstrate in public how he understood mathematics. It was an open lesson in the grasping of mathematics by one of the most amazing mathematicians of our time. This role could be only be played under the most favorable conditions: the genre dictates the rules of the game, which are not always very convenient for the listeners. This means, for example, that the leader follows only his own intuition in the final choice of the topics of the talks, interrupts them with comments and questions (a privilege not granted to other participants) [....] All this is done with extraordinary generosity, a true passion for mathematics.

Let me recall some of the stage director's strategems. An important feature were improvisations of various kinds. The course of the seminar could change dramatically at any moment. Another important mise en scene involved the "trial listener" game, in which one of the participants (this could be a student as well as a professor) was instructed to keep informing the seminar of his understanding of the talk, and whenever that information was negative, that part of the report would be repeated. A well-qualified trial listener could usually feel when the head of the seminar wanted an occasion for such a repetition. Also, Gelfand himself had the faculty of being "unable to understand" in situations when everyone around was sure that everything is clear. What extraordinary vistas were opened to the listeners, and sometimes even to the mathematician giving the talk, by this ability not to understand. Gelfand liked that old story of the professor complaining about his students: "Fantastically stupid students - five times I repeat proof, already I understand it myself, and still they don't get it."

It has remained beyond my understanding how Gelfand could manage all that physically for so many hours. Formally the seminar was supposed to begin at 6 pm, but usually started with an hour's delays. I am convinced that the free conversations before the actual beginning of the seminar were part of the scenario. The seminar would continue without any break until 10 or 10:30 (I have heard that before my time it was even later). The end of the seminar was in constant conflict with the rules and regulations of Moscow State University. Usually at 10 pm the cleaning woman would make her appearance, wishing to close the proceedings to do her job. After the seminar, people wishing to talk to Gelfand would hang around. The elevator would be turned off, and one would have to find the right staircase, so as not to find oneself stuck in front of a locked door, which meant walking back up to the 14th (where else but in Russia is the locking of doors so popular!). The next riddle was to find the only open exit from the building. Then the last problem (of different levels of difficulty for different participants) - how to get home on public transportation, at that time in the process of closing up. Seeing Gelfand home, the last mathematical conversations would conclude the seminar's ritual. Moscow at night was still safe and life seemed so unbelievably beautiful!

http://www.math.rutgers.edu/home/gelfand/

#geometry  ___

posted image

2016-05-30 16:00:05 (153 comments; 113 reshares; 332 +1s; )Open 

Let us read what we paid for

Imagine a business like this: you get highly trained experts to give you their research for free... and then you sell it back to them.  Of course these experts need equipment, and they need to earn a living... so you get taxpayers to foot the bill.  

And if the taxpayers want to actually read the papers they paid for?   Then you charge them a big fee!

It's not surprising that with this business model, big publishers are getting rich while libraries go broke.  Reed-Elsevier has a 37% profit margin!

But people are starting to fight back — from governments to energetic students like ‎Alexandra Elbakyan here.

On Friday, the Competitiveness Council —a gathering of European ministers of science, innovation, trade, and industry—said that by 2020, all publicly funded scientific papers published in Europeshould be ma... more »

Let us read what we paid for

Imagine a business like this: you get highly trained experts to give you their research for free... and then you sell it back to them.  Of course these experts need equipment, and they need to earn a living... so you get taxpayers to foot the bill.  

And if the taxpayers want to actually read the papers they paid for?   Then you charge them a big fee!

It's not surprising that with this business model, big publishers are getting rich while libraries go broke.  Reed-Elsevier has a 37% profit margin!

But people are starting to fight back — from governments to energetic students like ‎Alexandra Elbakyan here.

On Friday, the Competitiveness Council —a gathering of European ministers of science, innovation, trade, and industry—said that by 2020, all publicly funded scientific papers published in Europe should be made immediately free for everyone to read. 

This will start a big fight, and it may take longer than 2020.   But Alexandra Elbakyan isn't waiting around.

In 2011, as a computer science grad student in Kazakhstan, she got sick of paying big fees to read science papers.  She set up SciHub, a pirate website that steals papers from the publishers and sets them free.

SciHub now has 51,000,000 papers in its database.  In October 2015, Elsevier sued them.  In November, their domain name was shut down.  But they popped up somewhere else.  By February, people were downloading 200,000 papers per day.   Even scientists with paid access to the publisher's databases are starting to use SciHub, because it's easier to use.

Clearly piracy is the not the ultimate solution. Elbakyan now lives in an undisclosed location, to avoid being extradited.  But she gave the world a much-needed kick in the butt.   The old business model of get smart people to work for free and sell the product back to them is on its way out.

For more, read:

John Bohannon, Who's downloading pirated papers? Everyone, Science, 28 April 2016, http://www.sciencemag.org/news/2016/04/whos-downloading-pirated-papers-everyone

and especially the SciHub Twitter feed:

https://twitter.com/Sci_Hub

Also read this:

Martin Enserink, In dramatic statement, European leaders call for ‘immediate’ open access to all scientific papers by 2020, Science,
27 May 2016, http://www.sciencemag.org/news/2016/05/dramatic-statement-european-leaders-call-immediate-open-access-all-scientific-papers

The key word here is immediate - right now the US lets the journals sit on publicly funded papers for a year.  The Dutch government is really pushing this!  Congratulations to them!

#openaccess  ___

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2016-05-27 15:01:48 (75 comments; 35 reshares; 169 +1s; )Open 

The world's most long-winded proof

In the 1980s, the famous mathematician Ronald Graham asked if it's possible to color each positive integer either red or blue, so that no triple of integers a, b and c obeying Pythagoras’ famous equation:

a² + b² = c²

all have the same color.  He offered a prize of $100.

Now it's been solved!  The answer is no.  You can do it for numbers up to 7824, and a solution is shown in this picture.  But you can't do it for numbers up to 7825.

To prove this, you could try all the ways of coloring these numbers and show that nothing works.  Unfortunately that would require trying

3 628 407 622 680 653 855 043 364 707 128 616 108 257 615 873 380 491 654 672 530 751 098 578 199 115 261 452 571 373 352 277 580 182 512 704 196 704 700 964 418 214 007 274 963 650 268 320 833 348 358055 727 80... more »

The world's most long-winded proof

In the 1980s, the famous mathematician Ronald Graham asked if it's possible to color each positive integer either red or blue, so that no triple of integers a, b and c obeying Pythagoras’ famous equation:

a² + b² = c²

all have the same color.  He offered a prize of $100.

Now it's been solved!  The answer is no.  You can do it for numbers up to 7824, and a solution is shown in this picture.  But you can't do it for numbers up to 7825.

To prove this, you could try all the ways of coloring these numbers and show that nothing works.  Unfortunately that would require trying

3 628 407 622 680 653 855 043 364 707 128 616 108 257 615 873 380 491 654 672 530 751 098 578 199 115 261 452 571 373 352 277 580 182 512 704 196 704 700 964 418 214 007 274 963 650 268 320 833 348 358 055 727 804 748 748 967 798 143 944 388 089 113 386 055 677 702 185 975 201 206 538 492 976 737 189 116 792 750 750 283 863 541 981 894 609 646 155 018 176 099 812 920 819 928 564 304 241 881 419 294 737 371 051 103 347 331 571 936 595 489 437 811 657 956 513 586 177 418 898 046 973 204 724 260 409 472 142 274 035 658 308 994 441 030 207 341 876 595 402 406 132 471 499 889 421 272 469 466 743 202 089 120 267 254 720 539 682 163 304 267 299 158 378 822 985 523 936 240 090 542 261 895 398 063 218 866 065 556 920 106 107 895 261 677 168 544 299 103 259 221 237 129 781 775 846 127 529 160 382 322 984 799 874 720 389 723 262 131 960 763 480 055 015 082 441 821 085 319 372 482 391 253 730 679 304 024 117 656 777 104 250 811 316 994 036 885 016 048 251 200 639 797 871 184 847 323 365 327 890 924 193 402 500 160 273 667 451 747 479 728 733 677 070 215 164 678 820 411 258 921 014 893 185 210 250 670 250 411 512 184 115 164 962 089 724 089 514 186 480 233 860 912 060 039 568 930 065 326 456 428 286 693 446 250 498 886 166 303 662 106 974 996 363 841 314 102 740 092 468 317 856 149 533 746 611 128 406 657 663 556 901 416 145 644 927 496 655 933 158 468 143 482 484 006 372 447 906 612 292 829 541 260 496 970 290 197 465 492 579 693 769 880 105 128 657 628 937 735 039 288 299 048 235 836 690 797 324 513 502 829 134 531 163 352 342 497 313 541 253 617 660 116 325 236 428 177 219 201 276 485 618 928 152 536 082 354 773 892 775 152 956 930 865 700 141 446 169 861 011 718 781 238 307 958 494 122 828 500 438 409 758 341 331 326 359 243 206 743 136 842 911 727 359 310 997 123 441 791 745 020 539 221 575 643 687 646 417 117 456 946 996 365 628 976 457 655 208 423 130 822 936 961 822 716 117 367 694 165 267 852 307 626 092 080 279 836 122 376 918 659 101 107 919 099 514 855 113 769 846 184 593 342 248 535 927 407 152 514 690 465 246 338 232 121 308 958 440 135 194 441 048 499 639 516 303 692 332 532 864 631 075 547 542 841 539 848 320 583 307 785 982 596 093 517 564 724 398 774 449 380 877 817 714 717 298 596 139 689 573 570 820 356 836 562 548 742 103 826 628 952 649 445 195 215 299 968 571 218 175 989 131 452 226 726 280 771 962 970 811 426 993 797 429 280 745 007 389 078 784 134 703 325 573 686 508 850 839 302 112 856 558 329 106 490 855 990 906 295 808 952 377 118 908 425 653 871 786 066 073 831 252 442 345 238 678 271 662 351 535 236 004 206 289 778 489 301 259 384 752 840 495 042 455 478 916 057 156 112 873 606 371 350 264 102 687 648 074 992 121 706 972 612 854 704 154 657 041 404 145 923 642 777 084 367 960 280 878 796 437 947 008 894 044 010 821 287 362 106 232 574 741 311 032 906 880 293 520 619 953 280 544 651 789 897 413 312 253 724 012 410 831 696 803 510 617 000 147 747 294 278 502 175 823 823 024 255 652 077 422 574 922 776 413 427 073 317 197 412 284 579 070 292 042 084 295 513 948 442 461 828 389 757 279 712 121 164 692 705 105 851 647 684 562 196 098 398 773 163 469 604 125 793 092 370 432

possibilities.  But recently, three mathematicians cleverly figured out how to eliminate most of the options.  That left fewer than a trillion to check!  

So they spent 2 days on a supercomputer, running 800 processors in parallel, and checked all the options.  None worked.   They verified their solution on another computer.

This is the world's biggest proof: it's 200 terabytes long!  That's about equal to all the digitized text held by the US Library of Congress.  There's also a 68-gigabyte digital signature - sort of a proof that a proof exists - if you want to skim it.

It's interesting that these 200 terabytes were used to solve a yes-or-no question, whose answer takes a single bit to state: no.

I'm not sure breaking the world's record for the longest proof is something to be proud of.  Mathematicians prize short, elegant proofs.   I bet a shorter proof of this result will eventually be found.

Still, it's fun that we can do such things.   Here's a story about the proof:

http://www.nature.com/news/two-hundred-terabyte-maths-proof-is-largest-ever-1.19990

and here's the actual paper:

• Marijn J. H. Heule, Oliver Kullmann and Victor W. Marek, Solving and verifying the Boolean Pythagorean triples problem via cube-and-conquer, http://arxiv.org/abs/1605.00723.

The cube-and-conquer paradigm is a "hybrid SAT method for hard problems, employing both look-ahead and CDCL solvers"... whatever that means.  It would be interesting to learn about this.  But it's time for breakfast!

Anyone who makes a joke about Fermat's remark:

"I have discovered a truly marvellous proof of this, which this margin is too narrow to contain."

loses 10 points, for not reading my whole post.

#bigness  ___

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