Test CircleCount PRO now!
Login now

Not your profile? Login and get free access to your reports and analysis.

Tags

Sign in

The following tags have been added by users of CircleCount.com.
You can login on CircleCount to add more tags here.

  • Science
  • Scientists

Are you missing a tag in the list of available tags? You can suggest new tags here.

Login now

Do you want to see a more detailed chart? Check your settings and define your favorite chart type.

Or click here to get the detailed chart only once.

Shared Circles including John Baez

Shared Circles are not available on Google+ anymore, but you can find them still here.

The Google+ Collections of John Baez

New!
Login and checkout your own profile to see the average response per collection.
Or check out how it looks like on the profile page of +CircleCount.

Looks like this is your profile but we haven't loaded your posts yet to show you here the average numbers per collection.
Just open your dashboard and let the server work for you.

Activity

Average numbers for the latest posts (max. 50 posts, posted within the last 4 weeks)

26
comments per post
14
reshares per post
93
+1's per post

2,431
characters per posting

Top posts in the last 50 posts

Most comments: 160

posted image

2017-04-19 15:02:12 (160 comments; 9 reshares; 107 +1s; )Open 

Losing My Patience with Google+

Over the last six months or so I have watched as the quality of engagement here on Google+ has steadily declined. I have watched my follower count fluctuate and flatline. I have watched as people I used to engage with quite a bit here have left or dramatically scaled back their investments of time here. And yes, I have seen my own enthusiasm for investing time here wane significantly.

I ask myself why and the answers are never as simple as I would like. In the end though, I have come to the sad conclusion that the real thing that is killing Google+ is just plain bad management.

Lack of Attention
One gets the real sense that many of the people now charged with running Google+ don't really understand what it was that once made this service so good in its early days. Indeed, one gets the sense that few of the people... more »

Most reshares: 50

posted image

2017-05-07 23:46:15 (24 comments; 50 reshares; 164 +1s; )Open 

Juggling roots

As you change the coefficients of a polynomial, its roots move around. This is a surprisingly good source of fun for mathematicians of all ages.

This animation by twocubes shows the five roots of

x⁵ + tx³ + 1

moving around as the number t travels around a circle of radius 2 centered at the origin in the complex plane. See more here:

http://curiosamathematica.tumblr.com/post/140731259824/animation-by-twocubes-showing-the-roots-of-the

I think the contours lines are curves where the absolute value of this function is constant, with darker shades where it's smaller, and black where it's zero.

A lot of interesting things in math happen when you have two ways of viewing the same situation: then you can ask how a change in one view corresponds to a change in the other view. The two main waysto... more »

Most plusones: 202

posted image

2017-05-18 05:00:51 (32 comments; 20 reshares; 202 +1s; )Open 

Wheels within wheels

This beautiful animation by an anonymous Hungarian math grad student illustrates an amazing result of Jakob Steiner. Namely: if you can snugly fit some circles inside one circle and outside another, you can move these circles around while they stay touching! They may need to change size, though.

Just for fun, this animation goes ahead and recursively uses the same pattern inside each of the smaller circles, ad infinitum.

This result by Steiner, proved in the 1800s, is usually called Steiner's porism.

What the heck is a ‘porism’?

This is one of those scary Greek math words like ‘syzygy’ and ‘plethysm’ — words that nobody ever seems to explain in a clear, intuitive way. It’s not promising that the Wikipedia entry for ‘porism’ begins:

The subject of porisms is perplexed by themultitude of differ... more »

Latest 50 posts

posted image

2017-05-21 04:34:49 (25 comments; 7 reshares; 78 +1s; )Open 

Return of the alien megastructures?

Whenever a news article about science asks a yes-or-no question, the answer is probably not.

That said, the news is still exciting! Tabby's star occasionally gets much dimmer in a very irregular way. We don't know a good reason a star of this kind should do this... so one theory is that a civilization is engaged in some big engineering project that occasionally block the light from this star.

Regardless of the explanation, a mysterious phenomenon like this is lots of fun. Unfortunately, when people discovered this and got really interested, the star stopped doing it's thing!

Until two days ago, March 19th, when the star's discoverer, Tabetha Boyajian, tweeted:

#TabbysStar IS DIPPING! OBSERVE!! @NASAKepler @LCO_Global @keckobservatory @AAVSO @nexssinfo @NASA @NASAHubble... more »

Return of the alien megastructures?

Whenever a news article about science asks a yes-or-no question, the answer is probably not.

That said, the news is still exciting! Tabby's star occasionally gets much dimmer in a very irregular way. We don't know a good reason a star of this kind should do this... so one theory is that a civilization is engaged in some big engineering project that occasionally block the light from this star.

Regardless of the explanation, a mysterious phenomenon like this is lots of fun. Unfortunately, when people discovered this and got really interested, the star stopped doing it's thing!

Until two days ago, March 19th, when the star's discoverer, Tabetha Boyajian, tweeted:

#TabbysStar IS DIPPING! OBSERVE!! @NASAKepler @LCO_Global @keckobservatory @AAVSO @nexssinfo @NASA @NASAHubble @Astro_Wright @BerkeleySETI

Jason Wright, an astronomer at Penn State who is studying this star, wrote:

ALERT:@tsboyajian's star is dipping

This is not a drill.

Astro tweeps on telescopes in the next 48 hours: spectra please!

I don't know what a 'tweep' is - something like a nerd?

The graph in my post was put out by Boyajian in another tweet - it shows the luminosity dropping by 2% all of a sudden.

Here's more of the story, from Space.com:

Professional-grade telescopes typically schedule observing time weeks or months in advance, so Wright and his colleagues knew their observations would have to come at the behest of colleagues who were already using the telescopes for other projects.

"We need to have a network of people around the world that are ready to jump on [and observe it]," Wright said. "Fortunately, Tabby's star is not too faint and so there are a lot of observers and telescopes … that have graciously agreed to take some time out of their science to grab a spectrum for us [tonight]."

Wright said the call had gone out to amateur as well as professional astronomers to observe Boyajian's star during this dimming period. The largest and most powerful telescopes that will heed the call are the twin 10-meter telescopes at the W.H. Keck Observatory in Hawaii. The team is working to gain observing time on at least three other large telescopes on the U.S., according to Wright.

The Breakthrough Listen initiative, which searches for signs of intelligent life in the universe, has also taken an interest in the star and will be observing it with the Automated Planet Finder telescope at Lick Observatory in California, according to Andrew Siemion, director or the Berkeley SETI Research Center, said in the webcast.

"It's Super Bowl Sunday," Siemion said of the atmosphere at the during the webcast. "There's a palpable tension."

Breakthrough and the Berkeley center are now trying to get some observing time on the Green Bank radio telescope in West Virginia, according to Siemion.

For more, read the article on Space.com:

http://www.space.com/36925-alien-megastructure-star-dimming-again.html

For more much more, check out Jason Wright's YouTube channel:

https://www.youtube.com/watch?v=eYpIGZS8nJc

Here you can learn how various telescopes will study the star's dimming in the ultraviolet, infrared and so on, and how this will help us decide between different explanations: the 'alien megastructure' theory, the 'giant comets' theory, the 'infalling gas and dust' theory, the 'mysteriously variable star' theory, and the 'distant object blocking the star' theory.

#astronomy___

posted image

2017-05-20 08:46:27 (45 comments; 7 reshares; 74 +1s; )Open 

The power of 12

This morning I was having breakfast before my talk at Hong Kong Mathematical Society, all alone because Lisa had gone to Guangzhou with some friends who play the gu chin. Roger Howe walked by – he's a mathematician at Yale who is visiting here. He works on group theory, so it's not surprising that when I told him I'd be talking about the dodecahedron and icosahedron, he had something interesting to say.

He said there are some deep connections between the Platonic solids and the number 12 – connections that deserve to be better understood, and exploited. I'll pose them as puzzles:

Puzzle 1. What does the regular tetrahedron have 12 of?

Puzzle 2. What does the cube have 12 of?

Puzzle 3. What does the regular dodecahedron have 12 of?

Puzzle 4. How can you set up abij... more »

The power of 12

This morning I was having breakfast before my talk at Hong Kong Mathematical Society, all alone because Lisa had gone to Guangzhou with some friends who play the gu chin. Roger Howe walked by – he's a mathematician at Yale who is visiting here. He works on group theory, so it's not surprising that when I told him I'd be talking about the dodecahedron and icosahedron, he had something interesting to say.

He said there are some deep connections between the Platonic solids and the number 12 – connections that deserve to be better understood, and exploited. I'll pose them as puzzles:

Puzzle 1. What does the regular tetrahedron have 12 of?

Puzzle 2. What does the cube have 12 of?

Puzzle 3. What does the regular dodecahedron have 12 of?

Puzzle 4. How can you set up a bijection between the 12 things of the tetrahedron and the 12 things of the cube?

Puzzle 5. How can you set up a bijection between the 12 things of the cube and the 12 things of the dodecahedron?

Some of these are easier than others!

While you're thinking about these puzzles, here is some music to listen to - a nice live performance of Steve Reich's Electric Counterpoint by Mats Bergström.

Puzzle 6. What does this music have 12 of?

And for the übernerds out there:

Puzzle 7. What do modular forms have to do with the number 12, and how are they related to the tetrahedron?

#geometry___

posted image

2017-05-18 05:00:51 (32 comments; 20 reshares; 202 +1s; )Open 

Wheels within wheels

This beautiful animation by an anonymous Hungarian math grad student illustrates an amazing result of Jakob Steiner. Namely: if you can snugly fit some circles inside one circle and outside another, you can move these circles around while they stay touching! They may need to change size, though.

Just for fun, this animation goes ahead and recursively uses the same pattern inside each of the smaller circles, ad infinitum.

This result by Steiner, proved in the 1800s, is usually called Steiner's porism.

What the heck is a ‘porism’?

This is one of those scary Greek math words like ‘syzygy’ and ‘plethysm’ — words that nobody ever seems to explain in a clear, intuitive way. It’s not promising that the Wikipedia entry for ‘porism’ begins:

The subject of porisms is perplexed by themultitude of differ... more »

Wheels within wheels

This beautiful animation by an anonymous Hungarian math grad student illustrates an amazing result of Jakob Steiner. Namely: if you can snugly fit some circles inside one circle and outside another, you can move these circles around while they stay touching! They may need to change size, though.

Just for fun, this animation goes ahead and recursively uses the same pattern inside each of the smaller circles, ad infinitum.

This result by Steiner, proved in the 1800s, is usually called Steiner's porism.

What the heck is a ‘porism’?

This is one of those scary Greek math words like ‘syzygy’ and ‘plethysm’ — words that nobody ever seems to explain in a clear, intuitive way. It’s not promising that the Wikipedia entry for ‘porism’ begins:

The subject of porisms is perplexed by the multitude of different views which have been held by geometers as to what a porism really was and is.

In brief, a porism is something in between a ‘problem’ and a ‘theorem’. Here's what Wikipedia says:

The older geometers regarded a theorem as directed to proving what is proposed, a problem as directed to constructing what is proposed, and finally a porism as directed to finding what is proposed.

Got it?

The anonymous Hungarian math grad student has a fun page on Tumblr:

http://szimmetria-airtemmizs.tumblr.com/

He writes:

Hi there!

I am a Hungarian math student, currently doing my master degree at Eötvös Loránd University in Budapest. In my free time I like to draw mathematical stuff like fractals, tillings, tessellations, polyhedrons and so on.

I usually use the following programs to create them: Processing, Geogebra, Gimp, Inksckape. If you want to do similar pictures this is a good place to start: processing.org

I also organize math camps and math competitions in Hungary. I usually work with a really good foundation called the “The joy of thinking foundation”. If you are interested you can find more information here:

http://agondolkodasorome.hu/en/

If you have any questions feel free to ask :)

I asked his name.

Since I don't know anything more about this student, let me tell you about Jakob Steiner. He did a lot of fundamental work in projective geometry in the 1800s. A contemporary described him this:

He is a middle-aged man, of pretty stout proportions, has a long intellectual face, with beard and moustache and a fine prominent forehead, hair dark rather inclining to turn grey. The first thing that strikes you on his face is a dash of care and anxiety, almost pain, as if arising from physical suffering - he has rheumatism. He never prepares his lectures beforehand. He thus often stumbles or fails to prove what he wishes at the moment, and at every such failure he is sure to make some characteristic remark.

Here is some information about his porism:

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

A Steiner chain is a ring of circles, all touching, that fit snugly inside one circle and outside another.

#geometry___

posted image

2017-05-17 12:08:49 (0 comments; 3 reshares; 50 +1s; )Open 

Trump goes down... and we're all laughing

Bill Maher does a great job of explaining Trump's wacky antics last week. You couldn't make this stuff up.

And Putin's saying "Oh shit. Time to deactivate his microchip."

Trump goes down... and we're all laughing

Bill Maher does a great job of explaining Trump's wacky antics last week. You couldn't make this stuff up.

And Putin's saying "Oh shit. Time to deactivate his microchip."___

posted image

2017-05-15 10:37:17 (38 comments; 24 reshares; 123 +1s; )Open 

The dodecahedron, the icosahedron and E8

The regular dodecahedron and icosahedron were not first found in nature: they were discovered by Greek mathematicians, and we first read of them in a text written by Plato. Felix Klein used them to solve the quintic equation. But this was just the first step toward a more remarkable discovery: they can be used to construct the E8 lattice - which last year was proved to give the densest packing of spheres in 8 dimensions!

On Saturday I'll give a talk about this - but you can see my slides now:

http://math.ucr.edu/home/baez/icosidodecahedron/

Even if you don't follow the math, the pictures should be fun.

It took me a while to prepare this talk, because I wanted to understand things more deeply - in particular, how E8 shows up when you do a minimal resolution of a Kleinian singularity. ... more »

The dodecahedron, the icosahedron and E8

The regular dodecahedron and icosahedron were not first found in nature: they were discovered by Greek mathematicians, and we first read of them in a text written by Plato. Felix Klein used them to solve the quintic equation. But this was just the first step toward a more remarkable discovery: they can be used to construct the E8 lattice - which last year was proved to give the densest packing of spheres in 8 dimensions!

On Saturday I'll give a talk about this - but you can see my slides now:

http://math.ucr.edu/home/baez/icosidodecahedron/

Even if you don't follow the math, the pictures should be fun.

It took me a while to prepare this talk, because I wanted to understand things more deeply - in particular, how E8 shows up when you do a minimal resolution of a Kleinian singularity. Now that I understand it, I want to blog about it! But not right now.

In case you're in Hong Kong:

My talk will be at 10:50 am on Saturday May 20th in Lecture Theatre G at the Hong Kong University of Science and Technology. It's part of the Annual General Meeting of the Hong Kong Mathematical Society, and you can see the program here:

http://www6.cityu.edu.hk/ma/hkms/AGM_May2017.pdf

I'm having lots of fun here in Hong Kong, and I want to blog about that too. But again, not right now!

This picture, prepared by +Abdelaziz Nait Merzouk especially for my talk, shows Klein's icosahedral function - a function on the sphere that doesn't change when you do a rotation of the icosahedron. Klein used this to solve the quintic equation.

#geometry
___

posted image

2017-05-12 03:28:09 (12 comments; 2 reshares; 33 +1s; )Open 

Be nice to your mom... and give a monarch some milk!

The National Resources Defense Council will send your mom a mother's day card and plant a milkweed to help monarch butterflies! It's free and it's not annoying. Just click the link!

Monarch butterflies are amazing. Each fall, hundreds of millions of these black-and-orange butterflies fly over 4000 kilometers across the United States and Canada to wintering grounds in Mexico’s Sierra Madre Mountains.

Each winter people measure how much of these mountains get covered with monarchs. Each hectare is home to somewhere between 10 and 50 million of them! Last winter the butterflies covered 2.91 hectares.

Unfortunately, that's almost 30% less than the previous winter. And the monarch population has been in steady decline for the past 20 years — from over 20 hectares in 1997 to amer... more »

Be nice to your mom... and give a monarch some milk!

The National Resources Defense Council will send your mom a mother's day card and plant a milkweed to help monarch butterflies! It's free and it's not annoying. Just click the link!

Monarch butterflies are amazing. Each fall, hundreds of millions of these black-and-orange butterflies fly over 4000 kilometers across the United States and Canada to wintering grounds in Mexico’s Sierra Madre Mountains.

Each winter people measure how much of these mountains get covered with monarchs. Each hectare is home to somewhere between 10 and 50 million of them! Last winter the butterflies covered 2.91 hectares.

Unfortunately, that's almost 30% less than the previous winter. And the monarch population has been in steady decline for the past 20 years — from over 20 hectares in 1997 to a mere 0.67 hectares in 2014. After that it bounced up a little, but now it's continuing to shrink.

Why? There are probably lots of reasons, but here's one: heavy use of an herbicide called glyphosate (marketed by Monsanto as Roundup) has greatly diminished milkweed, a native wildflower that is the only food source for monarch caterpillars and the only plant on which monarch butterflies lay their eggs.

On top of that, the United States Environmental Protection Agency, now led by a guy who became famous for suing this agency, recently re-approved the registration of Enlist Duo, a combination of glyphosphate and 2-4,D, one of the active ingredients of Agent Orange.

The Natural Resource Defense Council is doing something about all this. They're working at the federal, state, and international level to secure limits on the use of toxic herbicides and create new milkweed habitat. They're petitioning UNESCO’s World Heritage Committee to upgrade its protection of monarch wintering habitat in Mexico. They're taking legal action against the EPA to win restrictions on toxic herbicides like glyphosphate. At the state level, they're working with officials to plant new milkweed habitat along the monarch’s migration route. For example, Illinois is going to plant milkweed along hundreds of miles of roadsides - and it's passed legislation to establish a monarch butterfly license plate that will fund this program.

My information here is paraphrased from this:

https://secure.nrdconline.org/site/SPageServer/?pagename=monarch_facts
___

posted image

2017-05-11 11:06:40 (0 comments; 2 reshares; 88 +1s; )Open 

Progress!

Progress!___

posted image

2017-05-11 05:06:29 (32 comments; 6 reshares; 55 +1s; )Open 

Binary icosahedral group

Here are 2 puzzles some of you could help me with. I think I know the answer from an indirect argument, but it would be nice to see it more directly.

The icosahedral group has 60 elements. It's the group of rotational symmetries of the icosahedron. It's also the group of even permutations of 5 things. It's generated by these 3 guys:

v: a 1/5 turn around some vertex,
e: a 1/2 turn around the center of an edge touching that vertex,
f: a 1/3 turn around the center of a face touching that vertex.

These obviously obey the relations

v^5 = e^2 = f^3 = 1

Puzzle 1: what other relations do we need to add to get a presentation of the icosahedral group. Will vef = 1 do the job? Is this relation even true? We may need to do the rotations in the correct directions to make... more »

Binary icosahedral group

Here are 2 puzzles some of you could help me with. I think I know the answer from an indirect argument, but it would be nice to see it more directly.

The icosahedral group has 60 elements. It's the group of rotational symmetries of the icosahedron. It's also the group of even permutations of 5 things. It's generated by these 3 guys:

v: a 1/5 turn around some vertex,
e: a 1/2 turn around the center of an edge touching that vertex,
f: a 1/3 turn around the center of a face touching that vertex.

These obviously obey the relations

v^5 = e^2 = f^3 = 1

Puzzle 1: what other relations do we need to add to get a presentation of the icosahedral group. Will vef = 1 do the job? Is this relation even true? We may need to do the rotations in the correct directions to make it true.

I'm really interested in another group, the binary icosahedral group, which has 120 elements. This is a nontrivial double cover of the icosahedral group. People tell me it has three generators v, e, f and these relations:

v^5 = e^2 = f^3 = vef

Given this, I think the answers to all three parts of my puzzle must be "yes". The reason is that v^5 and e^2 and f^3 all correspond to 360 degree rotations, which are the identity in the icosahedral group, but not in the binary icosahedral group. To get the icosahedral group we just need to add a relation saying that these equal 1.

The element vef should thus also be a 360 degree rotation, but I can't instantly see it and I'm too lazy to do a calculation because it should be obvious... especially because all the same stuff should work for the octahedron and tetrahedron, simply replacing the number "5" by "4" or "3". I could do it as a calculation using Coxeter groups, but it seems a bit irksome.

Here's a related puzzle:

Puzzle 2: Using just the relations

v^5 = e^2 = f^3 = vef

show that e^4 = 1.

This should be true, since e^4 is a 720 degree rotation, which is 1 even in the double cover of the rotation group! But the puzzle is to show this just by fiddling around with relations.

For more:

https://en.wikipedia.org/wiki/Binary_icosahedral_group#Presentation

#geometry___

posted image

2017-05-10 10:42:57 (57 comments; 8 reshares; 90 +1s; )Open 

Fractals at infinity

This gorgeous picture by +Abdelaziz Nait Merzouk shows a pattern in a curved 3-dimensional space called hyperbolic space. In hyperbolic space, there's there's more room as you go farther out than there is in ordinary flat space. So, you can create patterns that look very complicated in the distance. Indeed, they can look like fractals! And that's what we see here.

I could be wrong, but I'm willing to guess that this pattern is the order-4 dodecahedral honeycomb. That's a pattern made by sticking together dodecahedra with 4 meeting along each edge and 8 meeting at each vertex.

In ordinary flat space there's not enough room to get 4 regular dodecahedra to meet along an edge: the angles don't add up! But hyperbolic space has more room.

For more on the order-4 dodecahedral honeycomb, read... more »

diaphanous

Fractals are lurking from the infinity.

Licence for this picture: Creative commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) (https://creativecommons.org/licenses/by-sa/3.0/deed.en)___Fractals at infinity

This gorgeous picture by +Abdelaziz Nait Merzouk shows a pattern in a curved 3-dimensional space called hyperbolic space. In hyperbolic space, there's there's more room as you go farther out than there is in ordinary flat space. So, you can create patterns that look very complicated in the distance. Indeed, they can look like fractals! And that's what we see here.

I could be wrong, but I'm willing to guess that this pattern is the order-4 dodecahedral honeycomb. That's a pattern made by sticking together dodecahedra with 4 meeting along each edge and 8 meeting at each vertex.

In ordinary flat space there's not enough room to get 4 regular dodecahedra to meet along an edge: the angles don't add up! But hyperbolic space has more room.

For more on the order-4 dodecahedral honeycomb, read this:

https://en.wikipedia.org/wiki/Order-4_dodecahedral_honeycomb

You'll see a picture drawn by +Roice Nelson, and you can compare it with this one. Do they look the same? They don't look exactly the same, but I'm hoping they're just different styles of drawing the same thing!

From an artistic point of view, one of the nicest things about this picture is the lighting. It looks like sunlight shining through a paper screen ceiling! It makes me want to have a room like this.

As Abdelaziz says, it looks "diaphanous" - from Greek words that mean roughly "shining through".

#geometry

posted image

2017-05-09 07:20:27 (30 comments; 8 reshares; 47 +1s; )Open 

A dodecahedron in Hong Kong

I'm giving a talk at the annual meeting of the Hong Kong Mathematical Society. If anyone wants to help me by creating pretty images for this talk, that would be great. Here are some I could use:

1) A cube inscribed in a dodecahedron, preferably rotating. +Greg Egan gave me five cubes in a dodecahedron, as shown below. But while that's beautiful and I plan to use it, it's also a bit confusing. Something similar with just one would be nice.

2) An icosahedron inscribed in an almost-transparent sphere. This is to help explain how Felix Klein solved the quintic equation.

3) A picture of the function Klein invented to solve the quintic. It's a rational function of one complex variable that's invariant under the symmetries of the icosahedron. It equals 0 at the centers of the icosahedron's faces, 1... more »

A dodecahedron in Hong Kong

I'm giving a talk at the annual meeting of the Hong Kong Mathematical Society. If anyone wants to help me by creating pretty images for this talk, that would be great. Here are some I could use:

1) A cube inscribed in a dodecahedron, preferably rotating. +Greg Egan gave me five cubes in a dodecahedron, as shown below. But while that's beautiful and I plan to use it, it's also a bit confusing. Something similar with just one would be nice.

2) An icosahedron inscribed in an almost-transparent sphere. This is to help explain how Felix Klein solved the quintic equation.

3) A picture of the function Klein invented to solve the quintic. It's a rational function of one complex variable that's invariant under the symmetries of the icosahedron. It equals 0 at the centers of the icosahedron's faces, 1 on the midpoints of the edges, and infinity at the vertices. (More precisely, it has simple poles of residue 1 at the vertices.) There's a formula for it on page 66 of Shurman's book:

f(z) = (-z^{20} + 228 z^{15} - 494 z^{10} - 228 z^5 - 1)^3 /
(1728 z^5 (z^{10} + 11 z^5 - 1)^5)

Scary formula but beautiful function! Maybe you could draw a sphere with colors describing the phase of this function. I suppose you could also draw a kind of graph where instead of a sphere, there was a surface whose distance from the origin at the point z is 1 + |f(z)|. It would have spikes at the icosahedron's vertices.

You can see my talk so far here:

http://math.ucr.edu/home/baez/icosidodecahedron/

It's far from finished! It'll be more advanced than some of my previous talks on the icosahedron and dodecahedron. My first goal is to explain the geometric McKay correspondence connecting these shapes to E8.

Shurman's book is here, and I recommend it:

• Jerry Shurman, The Geometry of the Quintic, http://people.reed.edu/~jerry/Quintic/quintic.html

#geometry___

posted image

2017-05-07 23:46:15 (24 comments; 50 reshares; 164 +1s; )Open 

Juggling roots

As you change the coefficients of a polynomial, its roots move around. This is a surprisingly good source of fun for mathematicians of all ages.

This animation by twocubes shows the five roots of

x⁵ + tx³ + 1

moving around as the number t travels around a circle of radius 2 centered at the origin in the complex plane. See more here:

http://curiosamathematica.tumblr.com/post/140731259824/animation-by-twocubes-showing-the-roots-of-the

I think the contours lines are curves where the absolute value of this function is constant, with darker shades where it's smaller, and black where it's zero.

A lot of interesting things in math happen when you have two ways of viewing the same situation: then you can ask how a change in one view corresponds to a change in the other view. The two main waysto... more »

Juggling roots

As you change the coefficients of a polynomial, its roots move around. This is a surprisingly good source of fun for mathematicians of all ages.

This animation by twocubes shows the five roots of

x⁵ + tx³ + 1

moving around as the number t travels around a circle of radius 2 centered at the origin in the complex plane. See more here:

http://curiosamathematica.tumblr.com/post/140731259824/animation-by-twocubes-showing-the-roots-of-the

I think the contours lines are curves where the absolute value of this function is constant, with darker shades where it's smaller, and black where it's zero.

A lot of interesting things in math happen when you have two ways of viewing the same situation: then you can ask how a change in one view corresponds to a change in the other view. The two main ways to view a polynomial are its coefficients and its roots. I can imagine a program where these two views are side by side. You can move the coefficients around in the left side and see how the roots move around at right, or vice versa. For a polynomial of degree 5, dragging one coefficient around a circle in the left-hand view will create this animated image in the right-hand view.

(Be careful: the coefficients are an ordered list of numbers, while the roots are a multiset. Also, to get the roots of a polynomial to determine its coefficients, we should assume it's monic, meaning the first coefficient equals 1. Otherwise you can double all the coefficients without changing the roots.)

Thanks to +Henry Segerman for pointing this out. If any of you haven't seen his posts, it's time to check them out!

#geometry___

posted image

2017-05-06 08:16:13 (8 comments; 13 reshares; 95 +1s; )Open 

Phosphorus sulfides

When you combine phosphorus and sulfur, you get molecules with remarkable geometries. This is one.

I know 20 of these molecules, called phosphorus sulfides. You can see pictures of most on my blog article:

https://johncarlosbaez.wordpress.com/2017/05/05/phosphorus-sulfides/

Some strange facts:

1) They have between 2 and 10 sulfur atoms, but

2) all but one have exactly 4 phosphorus atoms, arranged in a tetrahedron!

3) Each phosphorus atom is connected to 3 or 4 other atoms, but

4) in all but one, each phosphorus is connected to at most one other phosphorus.

5) Each sulfur is connected to either 1 or 2 other atoms, and

6) a sulfur atom can only be connected to a phosphorus.

These strange facts lead to some interesting chemistry and math puzzles. Check... more »

Phosphorus sulfides

When you combine phosphorus and sulfur, you get molecules with remarkable geometries. This is one.

I know 20 of these molecules, called phosphorus sulfides. You can see pictures of most on my blog article:

https://johncarlosbaez.wordpress.com/2017/05/05/phosphorus-sulfides/

Some strange facts:

1) They have between 2 and 10 sulfur atoms, but

2) all but one have exactly 4 phosphorus atoms, arranged in a tetrahedron!

3) Each phosphorus atom is connected to 3 or 4 other atoms, but

4) in all but one, each phosphorus is connected to at most one other phosphorus.

5) Each sulfur is connected to either 1 or 2 other atoms, and

6) a sulfur atom can only be connected to a phosphorus.

These strange facts lead to some interesting chemistry and math puzzles. Check out my blog! Even if you don't care about the puzzles, you'll probably enjoy the pictures. The universe is full of patterns, and the simplest ones are usually pretty - it takes a certain amount of complexity for something to be really ugly.

#chemistry___

posted image

2017-05-04 14:30:26 (42 comments; 2 reshares; 53 +1s; )Open 

Bang!

This compound explodes if you touch it with a feather. In fact, it's the only compound so explosive that it can be set off by exposing it to small amounts of alpha radiation - that is, high-speed helium nuclei.

Puzzle 1: What is it?

Puzzle 2: When it explodes, what color smoke does it make?

Puzzle 3: If it's so unstable, how do you ever get enough of it in one place to explode?

#chemistry


Bang!

This compound explodes if you touch it with a feather. In fact, it's the only compound so explosive that it can be set off by exposing it to small amounts of alpha radiation - that is, high-speed helium nuclei.

Puzzle 1: What is it?

Puzzle 2: When it explodes, what color smoke does it make?

Puzzle 3: If it's so unstable, how do you ever get enough of it in one place to explode?

#chemistry
___

posted image

2017-05-03 04:09:42 (72 comments; 12 reshares; 70 +1s; )Open 

Tai chi versus mixed martial arts

You've probably seen those Chinese movies where fighters from one school of martial arts line up to battle a contender from another school. Now it's happening in real life!

You may not think of tai chi as a martial art – it looks more like a form of meditation. For some experts it becomes a fighting style. But recently the mixed martial arts fighter Xu Xiadong has been saying it's obsolete. This got tai chi masters angry! So on Monday they decided to settle this dispute with a fight: Xu Xiadong versus Wei Lei, a practitioner of the Yang style of tai chi.

Xu started the fight in a boxing stance while Wei held his arms outstretched in a crane-like pose.

The two circled each other briefly before Xu, nicknamed “Madman” by fans for his fighting style, then went in for the jugular and quickly pummelledhis o... more »

Tai chi versus mixed martial arts

You've probably seen those Chinese movies where fighters from one school of martial arts line up to battle a contender from another school. Now it's happening in real life!

You may not think of tai chi as a martial art – it looks more like a form of meditation. For some experts it becomes a fighting style. But recently the mixed martial arts fighter Xu Xiadong has been saying it's obsolete. This got tai chi masters angry! So on Monday they decided to settle this dispute with a fight: Xu Xiadong versus Wei Lei, a practitioner of the Yang style of tai chi.

Xu started the fight in a boxing stance while Wei held his arms outstretched in a crane-like pose.

The two circled each other briefly before Xu, nicknamed “Madman” by fans for his fighting style, then went in for the jugular and quickly pummelled his opponent to the ground, swiftly ending the match.

It took just 10 seconds.

The fight was staged and live-streamed after the two debated the merits of traditional Chinese martial arts online.

Wei told the Legal Evening News that Xu had crossed the line by dismissing tai chi. “Since [Xu] insulted tai chi so strongly, including cursing at our ancestors, I thought there was no room for cooperation between us,” Wei was quoted as saying.

Following his quick victory over Wei – who claimed to be the founder of a “thunder style” of tai chi – Xu wrote on his microblog: “All of China’s martial arts masters were watching … I will do what I should do. Everyone should calmly use their independent thinking abilities.”

Wei responded to the match by saying: “I lost. Everyone who wanted to get in on the fun all saw it! I lost, but it is not a problem … I accept this result.”

So, all that meditation at least brought him serenity. But that's not the end of the story:

At least three traditional martial arts masters have picked up the gauntlet thrown down by mixed martial arts (MMA) fighter Xu ­Xiaodong, saying they were willing to face him in combat to defend their tactics and traditions.

But exponents of traditional martial arts said that even if the challengers lost in the ring against Xu, it would not mean their approach was inferior to the modern MMA way.

Hmm.

Xu, a trained kung fu free-combat sportsman who taught himself MMA, has claimed that traditional martial arts are outdated and only good for keeping in shape. In combat, free-style fighting or boxing was more practical, The Beijing News quoted him as saying on Monday.

Xu’s comments came after he took just 10 seconds to defeat tai chi master Wei Lei – who also calls himself Lei Lei – in a fight in Chengdu, Sichuan province, last week, reigniting debate over which approach is superior. Wei is a practitioner of the Yang style of tai chi, characterised by slow, steady movements.

Xu said on his microblog that he could take on two or three traditional martial artists and a number had already accepted.

Among Xu’s challengers were two tai chi masters Lu Xing and Wang Zhanhai, Guangzhou native Li Shangxian who specialises in the Shaolin Meihua Zhuang form of Chinese boxing, and Yi Long, a monk known for his martial arts prowess.

Lu told the Chengdu Business News that he wanted to teach Xu a lesson.

“He is deeply biased against traditional martial arts and his words were insulting. I challenged him so he could have a fresh perspective of tai chi and the true traditional martial arts,” said Lu, who specialises in a form of tai chi known as tuishou, or pushing hands.

Lu said he was 80 per cent sure of winning because tai chi masters had “an iron fist, air foot and iron back, which took more than 20 years of hard training”.

Xu’s form of martial arts was more about projecting an explosive force, he said.

Wang, a Henan native who practises the Chen style of tai chi, said he decided to fight Xu to silence online dissenters.

The Chen style of tai chi is characterised by a “silk-reeling” movement that alternates fast and slow motions and bursts of power.

Yi, the fighter monk, wrote on his microblog that he would not stand for the MMA fighter insulting traditional Chinese martial arts and “deceiving the public”.

Jiang Lugui, president of the Taohua Tai Chi Research Institute under the Sichuan Martial Arts Association, said tai chi had changed over time from a combat technique to a form of exercise.

“People practice martial arts not to kill but to cultivate a healthy body. Tai chi has largely developed into a competitive sport or exercise for health,” Jiang said.

“The practical nature of tai chi, to kill or overpower someone quickly, is no longer the reason people practise it.”

And that's a sense in which tai chi may truly be superior to mixed martial arts: not for fighting, but for self-cultivation. Still, I'm eager to see what happens next.

You can see the match between Xu Xiaodong and Wei Lei here:

https://www.youtube.com/watch?v=nUOXGQ0MqP0

Unfortunately it happens so fast the camera misses a lot of it!

All the quotes are from the South China Morning Post, which is the main paper in English here in Hong Kong.

#travel___

posted image

2017-05-02 12:30:51 (25 comments; 7 reshares; 116 +1s; )Open 

Diamondoids

I have a new favorite molecule: adamantane. Someone is ‘adamant’ if they are unshakeable, immovable, inflexible, unwavering, uncompromising, resolute, resolved, determined, firm, rigid, or steadfast. But ‘adamant’ is also the name of a legendary mineral - and the word comes from the same root as ‘diamond’.

The molecule adamantane is shown here. It's the simplest of the diamondoids: molecules made of carbon and hydrogen where the carbons are arranged just like a small portion of a diamond crystal!

For more pretty pictures of diamondoids, and some fun math puzzles about adamantane, read my blog article:

https://johncarlosbaez.wordpress.com/2017/05/02/diamondoids/

#chemistry

Diamondoids

I have a new favorite molecule: adamantane. Someone is ‘adamant’ if they are unshakeable, immovable, inflexible, unwavering, uncompromising, resolute, resolved, determined, firm, rigid, or steadfast. But ‘adamant’ is also the name of a legendary mineral - and the word comes from the same root as ‘diamond’.

The molecule adamantane is shown here. It's the simplest of the diamondoids: molecules made of carbon and hydrogen where the carbons are arranged just like a small portion of a diamond crystal!

For more pretty pictures of diamondoids, and some fun math puzzles about adamantane, read my blog article:

https://johncarlosbaez.wordpress.com/2017/05/02/diamondoids/

#chemistry___

posted image

2017-05-01 07:34:24 (0 comments; 31 reshares; 101 +1s; )Open 

Don't just march for climate truth - work for it

There were a lot of great marches on Saturday by folks who take climate change seriously. But marching is not enough! The problem, always deadly serious, got a tiny bit worse on April 19th when somebody gutted the US Interior Department's main webpage on this subject:

What was once a robust overview of the Interior's climate change priorities is now a pedestrian paragraph about the types of land the agency protects. Gone are the mentions of rising sea levels, worsening wildfires, and threatened wildlife. In fact, the entire page, which is just 101-words-long, only uses the term "climate change" once.

You can see the changes here:

https://motherboard.vice.com/en_us/article/the-interior-department-scrubbed-its-climate-change-page-doi-zinke

The situation is desperate... but... more »

Don't just march for climate truth - work for it

There were a lot of great marches on Saturday by folks who take climate change seriously. But marching is not enough! The problem, always deadly serious, got a tiny bit worse on April 19th when somebody gutted the US Interior Department's main webpage on this subject:

What was once a robust overview of the Interior's climate change priorities is now a pedestrian paragraph about the types of land the agency protects. Gone are the mentions of rising sea levels, worsening wildfires, and threatened wildlife. In fact, the entire page, which is just 101-words-long, only uses the term "climate change" once.

You can see the changes here:

https://motherboard.vice.com/en_us/article/the-interior-department-scrubbed-its-climate-change-page-doi-zinke

The situation is desperate... but not hopeless. The story below, pointed out by +Matt McIrvin, tells how one professional, paid denier changed his mind. I'll quote a bit:

Sharon Lerner: What did you think when you first encountered the concept of climate change back in the 1990s?

Jerry Taylor: From 1991 through 2000, I was a pretty good warrior on that front. I was absolutely convinced of the case for skepticism with regard to climate science and of the excessive costs of doing much about it even if it were a problem. I used to write skeptic talking points for a living.

SL: What was your turning point?

JT: It started in the early 2000s. I was one of the climate skeptics who do battle on TV and I was doing a show with Joe Romm. On air, I said that, back in 1988, when climate scientist James Hansen testified in front of the Senate, he predicted we’d see a tremendous amount of warming. I argued it’d been more than a decade and we could now see by looking at the temperature record that he wasn’t accurate. After we got done with the program and were back in green room, getting the makeup taken off, Joe said to me, “Did you even read that testimony you’ve just talked about?” And when I told him it had been a while, he said “I’m daring you to go back and double check this.” He told me that some of Hansen’s projections were spot on. So I went back to my office and I re-read Hanson’s testimony. And Joe was correct. So I then I talked to the climate skeptics who had made this argument to me, and it turns out they had done so with full knowledge they were being misleading.

SL: So that was it? You changed your mind?

JT: It was more gradual. After that, I began to do more of that due diligence, and the more I did, the more I found that variations on this story kept arising again and again. Either the explanations for findings were dodgy, sketchy or misleading or the underlying science didn’t hold up. Eventually, I tried to get out of the science narratives that I had been trafficking in and just fell back on the economics. Because you can very well accept that climate change exists and still find arguments against climate action because the costs of doing something are so great.

SL: And the economic case eventually crumbled, too?

JT: The first blow in that argument was offered by my friend Jonathan Adler, who was at the Competitive Enterprise Institute. Jon wrote a very interesting paper in which he argued that even if the skeptic narratives are correct, the old narratives I was telling wasn’t an argument against climate action. Just because the costs and the benefits are more or less going to be a wash, he said, that doesn’t mean that the losers in climate change are just going to have to suck it up so Exxon and Koch Industries can make a good chunk of money.

The final blow against my position, which caused me to crumble, was from a fellow named Bob Litterman, who had been the head of risk management at Goldman Sachs. Bob said, “The climate risks aren’t any different from financial risks I had to deal with at Goldman. We don’t know what’s going to happen in any given year in the market. There’s a distribution of possible outcomes. You have to consider the entire distribution of possible outcomes when you make decisions like this.” After he left my office, I said “there’s nothing but rubble here.”

It's a bit frustrating that the Earth's climate may depend on convincing people, one at a time, of well-established facts. But Jerry Taylor has some tips on how to do it:

JT: In our business, talking to Republican and conservative elites, talking about the science in a dispassionate, reasonable, non-screedy, calm, careful way is powerful, because a lot of these people have no idea that a lot of the things they’re trafficking in are either the sheerest nonsense or utterly disingenuous.

I also make the conservative case for climate change. We don’t call people conservative when they put all their chips on one number of a roulette wheel. That’s not conservative. It’s pretty frigging crazy. It’s dangerous, risky. Conservatives think this way about foreign policy. We know that if North Korea has a nuclear weapon, they’re probably not going to use it. But we don’t act as if that’s a certainty. We hedge our bets. Climate change is like that. We don’t know exactly what’s going to happen. Given that fact, shouldn’t we hedge?

SL: I frequently hear about Republican lawmakers who don’t believe their own climate denials. Do you know many people who are in that camp?

JT: I have talked to many of them in confidence. There are between 40 and 50 in the House and maybe 10 to 12 in the Senate. They’re all looking for a way out of the denialist penitentiary they’ve been put into by the Tea Party. But they’re not sure what the Republican response ought to look like exactly and when the political window is going to open.

Let's help open that window!

#climateaction___

posted image

2017-04-30 12:33:12 (21 comments; 2 reshares; 45 +1s; )Open 

Back in old Hong Kong!

Why "old" Hong Kong? One reason is that Hoagie Carmichael song, the Hong Kong Blues. It starts like this:

It's the story of a very unfortunate colored man
Who got arrested down in old Hong Kong
He got twenty years privilege taken away from him
When he kicked old Buddha's gong.

It's featured in the great Bogart-Bacall movie To Have and Have Not. You can see the scene here:

https://www.youtube.com/watch?v=SUn4DOGiY_A

It's a cheesy bit of orientalism made tolerable by Hoagie's charm. But Hong Kong is indeed full of history and mystery, so "old Hong Kong" sounds right.

Anyway, we're back! Today Lisa and I went to the jade market in Yau Ma Tei. Our favorite jade seller was not there: she's visiting relatives in China. Her husband was, and he... more »

Back in old Hong Kong!

Why "old" Hong Kong? One reason is that Hoagie Carmichael song, the Hong Kong Blues. It starts like this:

It's the story of a very unfortunate colored man
Who got arrested down in old Hong Kong
He got twenty years privilege taken away from him
When he kicked old Buddha's gong.

It's featured in the great Bogart-Bacall movie To Have and Have Not. You can see the scene here:

https://www.youtube.com/watch?v=SUn4DOGiY_A

It's a cheesy bit of orientalism made tolerable by Hoagie's charm. But Hong Kong is indeed full of history and mystery, so "old Hong Kong" sounds right.

Anyway, we're back! Today Lisa and I went to the jade market in Yau Ma Tei. Our favorite jade seller was not there: she's visiting relatives in China. Her husband was, and he showed us some nice white jade from Xinjiang – the wild west of China. This is getting rare these days, but we decided not to buy any until the woman comes back in 10 days. It gives us an excuse to postpone difficult – and an excuse to return.

We also took a look in the Tin Hau temple near the jade market. Tin Hau is the god of the sea, a favorite of sailors. But the little figures shown here are some of the sixty Tai Sui deities – one for each year in a 60-year cycle formed by multiplying the 12 signs of the zodiac by the 5 phases: wood (木 mù), fire (火 huǒ), earth (土 tǔ), metal (金 jīn) and water (水 shuǐ). Like many Chinese temples I've seen, this one has statues of all sixty. But how they look varies immensely from temple to temple!

Then we walked north to Mong Kok, a very busy area full of shops. It was densely packed with people – maybe because it's a long weekend with May Day coming on Monday?

Lisa was happy to see that the Mong Kok computer center, a building packed with useful small stores, has been reopened. We bought some crucial VGA/micro-D converters and went back to our hotel, exhausted but glad to be back in old Hong Kong.

#travel #hongkong___

posted image

2017-04-28 14:57:37 (22 comments; 24 reshares; 90 +1s; )Open 

Biology as information dynamics

Here's the talk I gave last week at the Stanford Complexity Group.

If biology is the study of self-replicating entities, and we want to understand the role of information, it makes sense to see how information theory is connected to the replicator equation — a simple but extremely general model of population dynamics for self-replicating entities.

But it's important to realize that the amount of new information you gain when you learn something should be measured relative to what you already believe. So, the relevant concept of information turns out to be the information of one probability distribution relative to another. So, I start with an explanation of relative information.

Then I show how this gives a new outlook on thermodynamics. Then I explain the replicator equation and show howr... more »

Biology as information dynamics

Here's the talk I gave last week at the Stanford Complexity Group.

If biology is the study of self-replicating entities, and we want to understand the role of information, it makes sense to see how information theory is connected to the replicator equation — a simple but extremely general model of population dynamics for self-replicating entities.

But it's important to realize that the amount of new information you gain when you learn something should be measured relative to what you already believe. So, the relevant concept of information turns out to be the information of one probability distribution relative to another. So, I start with an explanation of relative information.

Then I show how this gives a new outlook on thermodynamics. Then I explain the replicator equation and show how relative information lets us see evolution as a learning process Finally, I give a clearer, more general formulation of Fisher’s fundamental theorem of natural selection.

There were a lot of really interesting questions at the end of my talk. The audience picked up on lots of subtleties that I felt I'd glossed over in my talk.

#biology___

posted image

2017-04-27 14:56:29 (0 comments; 30 reshares; 193 +1s; )Open 

The first 100 days of failure

Good news: so far, many of Trump's wrongheaded impulses are being blocked by his inability to govern, together with a massive wall of opposition. Even better: as a 70-year-old man who doesn't listen to advice, he's not learning very fast. But we can't let down our guard. He may eventually figure out how to do something - or hand over control to someone who can.

Here's a good summary of his first 100 days, by David Leonhart.

Trump has made no significant progress on any major legislation. His health care bill is a zombie. His border wall is stalled. He’s only now releasing basic principles of a tax plan. Even his executive order on immigration is tied up in the courts. By contrast, George W. Bush and Ronald Reagan had made substantial progress toward passing tax cuts, and Barack Obama had passed, among othert... more »

The first 100 days of failure

Good news: so far, many of Trump's wrongheaded impulses are being blocked by his inability to govern, together with a massive wall of opposition. Even better: as a 70-year-old man who doesn't listen to advice, he's not learning very fast. But we can't let down our guard. He may eventually figure out how to do something - or hand over control to someone who can.

Here's a good summary of his first 100 days, by David Leonhart.

Trump has made no significant progress on any major legislation. His health care bill is a zombie. His border wall is stalled. He’s only now releasing basic principles of a tax plan. Even his executive order on immigration is tied up in the courts. By contrast, George W. Bush and Ronald Reagan had made substantial progress toward passing tax cuts, and Barack Obama had passed, among other things, a huge stimulus bill that also addressed education and climate policy.

Trump is far behind staffing his administration. Trump has made a mere 50 nominations to fill the top 553 positions of the executive branch, as of [last] Friday. That’s right: He hasn’t even nominated anyone for 90 percent of its top jobs. The average president since 1989 had nominated twice as many, according to the Partnership for Public Service.

Part of the reason is a lack of execution: The administration has been slow to make nominations. And part of the reason is who is being nominated: A disproportionate number of affluent investors and business executives with many potential conflicts of interest that require vetting. Either way, the effects are real. The executive branch can’t push through the president’s priorities if it doesn’t have his people in place.

The Trump administration is more nagged by scandal than any previous administration. No new administration has dealt with a potential scandal anywhere near as large or as distracting as the Russia investigation. It could recede over time, true. But it also could come to dominate the Trump presidency.

Trump has no clear foreign policy. Is he protectionist, as he appeared to be when starting a trade spat with Canada on [last] Tuesday, or a globalist, as he appeared when backing off his criticism of China? Is he an isolationist, an interventionist or some alternative? No one seems to know, which confuses allies and does a favor for rivals who would welcome diminished American influence.

Trump is by far the least popular new president in the modern polling era. His approval rating is just 41 percent, according to FiveThirtyEight. All other elected presidents since Roosevelt have had an approval rating of at least 53 percent after 100 days. (Gerald Ford was at 45 percent.) Some, including Obama, Reagan and Johnson, have been above 60 percent.

Trump’s low approval isn’t only a reflection of his struggles. It also becomes a cause of further struggles. Members of Congress aren’t afraid to buck an unpopular president, which helps explain the collapse of Trumpcare.

Obviously, Trump can claim some successes on his own terms. Most consequentially, he has named a Supreme Court justice who could serve for decades. Trump has also put in place some meaningful executive orders, on climate policy above all, and he has allied the federal government with the cause of white nationalism, as Jonathan Chait wrote.

Trump remains the most powerful person in the country, if not the world. It would be foolish for anyone to be complacent about what he can do. Yet by the modern standards of the office, he is a weak president off to a uniquely poor start.

This is a quote from here:

https://www.nytimes.com/2017/04/26/opinion/donald-trumps-first-100-days-the-worst-on-record.html



___

posted image

2017-04-25 14:14:40 (13 comments; 15 reshares; 113 +1s; )Open 

It would be strange to actually walk around her.

___It would be strange to actually walk around her.

posted image

2017-04-23 20:02:17 (34 comments; 12 reshares; 157 +1s; )Open 

I didn't go to the science march, but only because I'm always on the march for science.

___I didn't go to the science march, but only because I'm always on the march for science.

posted image

2017-04-23 07:06:38 (30 comments; 2 reshares; 23 +1s; )Open 

ⴰⵙⵇⵇⵉⵎ ⵏ ⵜⵎⵙⵙⴰⴳⵓⵔⵜ

ⵉⴳ ⵢⵓⵔⴰ ⵉⴷⵉⵙ ⵏ ⵛⴰ ⵏ ⵢⵉⵊⵊ ⴳ ⵡⴰⴳⵎⴰⵎⵏ ⵏ ⵓⵙⵇⵇⵉⵎ, ⵉⵥⴹⴰⵕ ⵓⵏⴱⴷⴰⴷ ⴰⴷ ⵉⵙⵜⵉ ⵉⵙⵎ ⵏ ⴽⵔⴰ ⵏ ⵢⴰⵏ ⵉⵣⵣⵔⵉ ⵜ ⵉ ⵓⴳⵍⵍⵉⴷ ⵃⵎⴰ ⴰⴷ ⵢⴰⵎⵥ ⵉⴷⵉⵙ ⴰⵏⵏ ⵢⵓⵔⴰⵏ.

ⵜⵜⵡⵓⵛⵏⵜ ⵉ ⵓⵙⵇⵇⵉⵎ ⵏ ⵜⵎⵙⵙⴰⴳⵓⵔⵜ ⵏ ⵓⵙⵉⵏⴰⴳ ⴰⴳⵍⴷⴰⵏ ⵏ ⵜⵓⵙⵙⵏⴰ ⵜⴰⵎⴰⵣⵉⵖⵜ ⵜⵉⵏⴱⴰⴹⵉⵏ ⵉⵎⴷⴰⵏ ⴱⴰⵛ ⴰⴷ ⵉⵙⵎⴷ ⵜⵉⵡⵓⵔⵉⵡⵉⵏ ⵏⵏⵙ. ⴷⴰ ⵉⵣⵣⵔⴰⵢ, ⵉⵎⵙⴰⵙⴰ ⵅⴼ ⵡⴰⵀⵉⵍ ⵏ ⵜⵡⵓⵔⵉ ⵏ ⵓⵙⵉⵏⴰⴳ ⴳ ⵢⵉⴷⵊ ⵏ ⵓⵙⴳⴳⵯⴰⵙ ⵏⵉⵖ ⴰⵟⵟⴰⵚ ⵏ ⵉⵙⴳⴳⵓⵙⴰ. ⵉⵥⵕ ⵉⵙⵇⵙⵉⵜⵏⵏⵏⴰ ⴰⵙ ⴷ ⵉⵣⵣⵔⵉ ⵓⴳⵍⵍⵉⴷ, ⵢⵓⵛⴰ ⴳⵉⵙⵏ ⵉⵎⵏⴰⴷⵏ ⵃⵎⴰ ⴰⴷ ⵉⴳⴳ ⵜⵉⵎⴰⵣⵣⴰⵍⵉⵏ ⵏⵏⵙ ⵉ ⵉⵙⵡⵓⵜⵜⴰ ⵓⴹⴰⵀⵉⵕ ⴰⴳⵍⴷⴰⵏ.

ⵉⵙⵔⵙ ⵓⵙⵇⵇⵉⵎ ⵏ ⵜⵎⵙⵙⴰⴳⵓⵔⵜ ⴳ ⵜⴷⵡⴰⵍⵉⵏ ⵜⵉⵎⵣⵡⵓⵔⴰ ⴰⵍⵓⴳⵏ ⴰⴳⵯⵏⵙⴰⵏ ⵏ ⵓⵙⵉⵏⴰⴳ, ⴷ ⵓⵙⵏⵜⵉ ⵏ ⵡⴰⵍⵣⴰⵣ ⵏⵏⵙ, ⴷ ⵡⴰⵍⵓⴳⵏ ⵏ ⵉⵎⵙⵡⵓⵔⴰ ⵏⵏⵙ.

ⵉⵙⵄⴷⴷⴰ ⵓⵏⴱⴷⴰⴷ ⵜⵉⵖⵜⴰⵙⵉⵏ ⵏ ⵓⵙⵉⵏⴰⴳ ⵉ ⵓⴳⵍⵍⵉⴷ ⴰⴼⴰⴷ ⴰⴷ ⵅⴰⴼⵙⵏⵜ ⵉⵙⵔⵙ ⴰⵣⵡⵍ ⵏⵏⵙ.

ⴷⴰ ⵉⵜⵜⵎⵓⵏ ⵓⵙⵇⵇⵉⵎ ⵙⵏⴰⵜ ⵏ ⵜⵡⴰⵍⴰⵜⵉⵏ ⴷⴳ ⵓⵙⴳⴳⵯⴰⵙ, ⵏⵖ ⵓⴳⴳⴰⵔ ⵙ ⵜⵓⵜⵜⵔⴰ ⵏⵓⵏⴱⴷⴰⴷⴰ, ⵏⵉⵖ ⵜⵉⵏ ⵓⴳⵍⵍⵉⴷ, ⵏⵉⵖ ⵙ ⵜⵓⵜⵜⵔⴰ ⵏ ⵓⴳⴰⵔ ⵏ ⵓⵣⴳⵏ ⵏ ⵡⴰⴳⵎⴰⵎⵏ ⵏ ⵓⵙⵙⵇⵉⵎ.

ⴷⴰ ⵉⵙⵔⵓⵙ ⵓⵏⴱⴷⴰⴷ ⵖⵓⵔ ⵓⴳⵍⵍⵉⴷ ⴰⵀⵉⵍ ⵏ ⵜⵡⵓⵔⵉ ⵏ ⵓⵙⵇⵇⵉⵎ.

ⵍⴰ ⵉⵜⵜⵎⵓⵏ ⵓⵙⵇⵇⵉⵎ ⵉⴳ ... more »

ⴰⵙⵇⵇⵉⵎ ⵏ ⵜⵎⵙⵙⴰⴳⵓⵔⵜ

ⵉⴳ ⵢⵓⵔⴰ ⵉⴷⵉⵙ ⵏ ⵛⴰ ⵏ ⵢⵉⵊⵊ ⴳ ⵡⴰⴳⵎⴰⵎⵏ ⵏ ⵓⵙⵇⵇⵉⵎ, ⵉⵥⴹⴰⵕ ⵓⵏⴱⴷⴰⴷ ⴰⴷ ⵉⵙⵜⵉ ⵉⵙⵎ ⵏ ⴽⵔⴰ ⵏ ⵢⴰⵏ ⵉⵣⵣⵔⵉ ⵜ ⵉ ⵓⴳⵍⵍⵉⴷ ⵃⵎⴰ ⴰⴷ ⵢⴰⵎⵥ ⵉⴷⵉⵙ ⴰⵏⵏ ⵢⵓⵔⴰⵏ.

ⵜⵜⵡⵓⵛⵏⵜ ⵉ ⵓⵙⵇⵇⵉⵎ ⵏ ⵜⵎⵙⵙⴰⴳⵓⵔⵜ ⵏ ⵓⵙⵉⵏⴰⴳ ⴰⴳⵍⴷⴰⵏ ⵏ ⵜⵓⵙⵙⵏⴰ ⵜⴰⵎⴰⵣⵉⵖⵜ ⵜⵉⵏⴱⴰⴹⵉⵏ ⵉⵎⴷⴰⵏ ⴱⴰⵛ ⴰⴷ ⵉⵙⵎⴷ ⵜⵉⵡⵓⵔⵉⵡⵉⵏ ⵏⵏⵙ. ⴷⴰ ⵉⵣⵣⵔⴰⵢ, ⵉⵎⵙⴰⵙⴰ ⵅⴼ ⵡⴰⵀⵉⵍ ⵏ ⵜⵡⵓⵔⵉ ⵏ ⵓⵙⵉⵏⴰⴳ ⴳ ⵢⵉⴷⵊ ⵏ ⵓⵙⴳⴳⵯⴰⵙ ⵏⵉⵖ ⴰⵟⵟⴰⵚ ⵏ ⵉⵙⴳⴳⵓⵙⴰ. ⵉⵥⵕ ⵉⵙⵇⵙⵉⵜⵏ ⵏⵏⴰ ⴰⵙ ⴷ ⵉⵣⵣⵔⵉ ⵓⴳⵍⵍⵉⴷ, ⵢⵓⵛⴰ ⴳⵉⵙⵏ ⵉⵎⵏⴰⴷⵏ ⵃⵎⴰ ⴰⴷ ⵉⴳⴳ ⵜⵉⵎⴰⵣⵣⴰⵍⵉⵏ ⵏⵏⵙ ⵉ ⵉⵙⵡⵓⵜⵜⴰ ⵓⴹⴰⵀⵉⵕ ⴰⴳⵍⴷⴰⵏ.

ⵉⵙⵔⵙ ⵓⵙⵇⵇⵉⵎ ⵏ ⵜⵎⵙⵙⴰⴳⵓⵔⵜ ⴳ ⵜⴷⵡⴰⵍⵉⵏ ⵜⵉⵎⵣⵡⵓⵔⴰ ⴰⵍⵓⴳⵏ ⴰⴳⵯⵏⵙⴰⵏ ⵏ ⵓⵙⵉⵏⴰⴳ, ⴷ ⵓⵙⵏⵜⵉ ⵏ ⵡⴰⵍⵣⴰⵣ ⵏⵏⵙ, ⴷ ⵡⴰⵍⵓⴳⵏ ⵏ ⵉⵎⵙⵡⵓⵔⴰ ⵏⵏⵙ.

ⵉⵙⵄⴷⴷⴰ ⵓⵏⴱⴷⴰⴷ ⵜⵉⵖⵜⴰⵙⵉⵏ ⵏ ⵓⵙⵉⵏⴰⴳ ⵉ ⵓⴳⵍⵍⵉⴷ ⴰⴼⴰⴷ ⴰⴷ ⵅⴰⴼⵙⵏⵜ ⵉⵙⵔⵙ ⴰⵣⵡⵍ ⵏⵏⵙ.

ⴷⴰ ⵉⵜⵜⵎⵓⵏ ⵓⵙⵇⵇⵉⵎ ⵙⵏⴰⵜ ⵏ ⵜⵡⴰⵍⴰⵜⵉⵏ ⴷⴳ ⵓⵙⴳⴳⵯⴰⵙ, ⵏⵖ ⵓⴳⴳⴰⵔ ⵙ ⵜⵓⵜⵜⵔⴰ ⵏ ⵓⵏⴱⴷⴰⴷⴰ, ⵏⵉⵖ ⵜⵉⵏ ⵓⴳⵍⵍⵉⴷ, ⵏⵉⵖ ⵙ ⵜⵓⵜⵜⵔⴰ ⵏ ⵓⴳⴰⵔ ⵏ ⵓⵣⴳⵏ ⵏ ⵡⴰⴳⵎⴰⵎⵏ ⵏ ⵓⵙⵙⵇⵉⵎ.

ⴷⴰ ⵉⵙⵔⵓⵙ ⵓⵏⴱⴷⴰⴷ ⵖⵓⵔ ⵓⴳⵍⵍⵉⴷ ⴰⵀⵉⵍ ⵏ ⵜⵡⵓⵔⵉ ⵏ ⵓⵙⵇⵇⵉⵎ.

ⵍⴰ ⵉⵜⵜⵎⵓⵏ ⵓⵙⵇⵇⵉⵎ ⵉⴳ ⵉⵍⵍⴰ ⵎⴰ ⵢⵓⴳⵔⵏ ⴰⵣⴳⵏ ⵏ ⵡⴰⴳⵎⴰⵎⵏ ⵏⵏⵙ (2/3). ⵉⵙⵙⵓⴼⵓⵖ ⵜⵉⵖⵜⴰⵙⵉⵏ ⵏⵏⵙ ⵎⴰⵍⴰ ⴷ ⴼⵍⵍⴰⵙⵏⵜ ⵉⵎⵙⴰⵙⴰ ⵓⴳⴳⴰⵔ ⵏ 2/3 ⵏ ⵡⴰⴳⵎⴰⵎⵏ ⵍⵍⵉ ⵉⵍⵍⴰⵏ ⴳ ⵓⴳⵔⴰⵡ.

ⵉⵣⵎⵎⵔ ⵓⵙⵇⵇⵉⵎ ⴰⴷ ⵢⴰⵎⵓ ⵜⵉⵔⵓⴱⴱⴰ ⵏ ⵜⵡⵓⵔⵉ ⴷ ⵜⵙⵇⵇⵉⵎⵉⵏ ⵏ ⴱⴷⴰ ⵏⵖ ⵜⵉⵣⵎⵣⴰⵏ ⴱⴰⵛ ⴰⴷ ⵉⴳ ⵜⵉⵎⴰⵣⵣⴰⵍⵉⵏ ⵏⵏⵙ. ⵉⵙⵡⵓⵜⵜⵓ ⵡⴰⵍⵓⴳⵏ ⴰⴳⵯⵏⵙⴰⵏ ⵏ ⵓⵙⵇⵇⵉⵎ. ⵎⴰⵛ ⵉⵇⵇⴰⵏ ⴷ ⴰⴷ ⵢⴰⵎⵓ ⵓⵙⵇⵇⵉⵎ ⵉⵛⵜ ⵏ ⵜⵙⵇⵇⵉⵎⵜ ⵏ ⵓⵙⵎⵍ ⴷ ⵜⵏⴼⵍⵓⵜ, ⵜⴰⵍⵍⵉ ⴰⴷ ⵉⵜⵜⵡⴰⵔⴰ ⵜⴰⵏⵏⴰⵢⵉⵏ ⵏ ⵓⵏⴱⴷⴰⴷ ⵉⵥⵍⵉⵏ ⵙ ⵓⵙⵜⴰⵢ ⵏ ⵡⴰⴳⵎⴰⵎⵏ ⵉⵎⴰⵢⵏⵓⵜⵏ ⵏⵏⵉ ⵔⴰ ⵢⵉⵍⵉ ⴳ ⵢⵉⴷⵉⵙ ⵏ ⵡⵉⵍⵍⵉ ⵎⵉ ⵜⵣⵔⵉ ⵜⵉⵣⵉ ⵏⵏⵙⵏ. ⵏⵉⵖ ⴰⵙⵜⴰⵢ ⵏ ⵡⴰⴳⵎⴰⵎⵏ ⵉ ⵔⴰⴷ ⵉⵜⵜⴰⵔⵉ ⵓⵙⵉⵏⴰⴳ ⴷⴳ ⵉⵎⵓⵙⵙⵓⵜⵏ ⵏ ⴱⵕⵕⴰ ⵏ ⵜⵎⵓⵔⵜ. ⵜⵓⵎⴰ ⵜⵙⵙⵇⵉⵎⵜ ⴰⴷ : ⵉⵏⴼⵍⴰⵙ ⵏ ⵜⵎⴰⵡⴰⵙⵉⵏ ⴷ ⵓⵎⵣⵡⴰⵔⵓ ⵏ ⵜⵙⴷⴰⵡⵉⵜ, ⴷ ⵓⵏⵎⵀⴰⵍ ⵏ ⵜⴽⴰⴷⵉⵎⵉⵢⵜ, ⴷ ⵙⴰ ⵡⴰⴳⵎⴰⵎⵏ ⴷⴰ ⵜⵏ ⵉⵙⵜⴰⵢ ⵓ___

posted image

2017-04-19 15:02:12 (160 comments; 9 reshares; 107 +1s; )Open 

Bye-bye, Google+ — but what next?

Google+ is sliding downhill. A couple years ago my posts would garner comments from lots of smart people, leading to long and deep discussions. These days only a few stalwarts remain — a skeleton crew. I've copied most of my posts here to my website and blog. I mainly post here out of inertia: for certain purposes, I haven't found anything better yet.

As for the reasons, I agree with +Gideon Rosenblatt's analysis. Also read the many comments on his post! But the more important question is: what to do now?

Instead of whining about our masters, we should be our own masters — and unleash our creative energies! A bottom-up approach, run by all of us, could be better than top-down corporate control. A diverse, flexible federation could be better than a single unified platform.

Has anyone heretried... more »

Losing My Patience with Google+

Over the last six months or so I have watched as the quality of engagement here on Google+ has steadily declined. I have watched my follower count fluctuate and flatline. I have watched as people I used to engage with quite a bit here have left or dramatically scaled back their investments of time here. And yes, I have seen my own enthusiasm for investing time here wane significantly.

I ask myself why and the answers are never as simple as I would like. In the end though, I have come to the sad conclusion that the real thing that is killing Google+ is just plain bad management.

Lack of Attention
One gets the real sense that many of the people now charged with running Google+ don't really understand what it was that once made this service so good in its early days. Indeed, one gets the sense that few of the people managing the service today even really use Google+. There are a few noteworthy exceptions like +Yonatan Zunger and +Leo Deegan, of course. I once made a circle with some 50+ Googlers who were once active here, and when I click on that stream, well, it feels a lot like a ghost town.

+Bradley Horowitz, the VP in charge of Streams, Photos and Sharing, (which is where Google+ sits within the Google org structure) hasn't posted here on Google+ in half a year.

Oh, and remember +Luke Wroblewski, who used to manage Google+ and would send out all those updates on the redesign? Well, he hasn't posted a single thing here in over 7 weeks (even though @lukew is quite active on Twitter). You know why? I just happened to check his LinkedIn profile, and he's apparently no longer managing Google+. I don't recall seeing any announcement of this change - just a sudden silence from the man perhaps most responsible for the UI makeover of Google+.

Rudderless and Un-resourced
That decision to remake the Google+ UI followed a long string of decisions going back to the separation of Photos and Hangouts, each of which have seriously hurt the service. I know there were probably some good reasons to move to the new, mobile-dominant (as opposed to "mobile-friendly") UI, but the lack of enduser empathy from deprecating all the old functionality really was pretty staggering. Much of it hasn't come back, and much of what has is so stripped down (e.g. Events, community moderation) that it isn't really that usable.

As users, we have been asked to be patient and to have faith in the new strategy. Because I have been such a huge fan of Google+ for so long, that is exactly what I have done. I've been patient. I've believed. Believed that some big, cool fix was coming down the pike that would not only fix all the problems caused by the UI decision, but actually start innovating again with some cool new functionality.

Yes, we got Collections, and they actually are quite useful even if they do need a lot of work still. But that's really about it. It's been a couple years now and the silence is stultifying.

And finally, it hit me:

Maybe this is it. Maybe Google has significantly curtailed its investments in this network. Maybe the management squandered the scarce resources it did have on a redesign that users weren't really even asking for. And maybe, just maybe, what we see right now is pretty much what we're going to get.

User Investments
And this is where I start to get really mad. Like many others here, I have invested a lot of personal time and energy building a following here. Like many of you, I have poured heart and soul into filling this place not just with great content, but also with a sense of community. I could have made those investments in Twitter or Facebook or reddit, but like many of you, I made them here. And now I'm starting to wonder how smart of a decision that was.

All of this is particularly raw right now because I'm starting to play around a bit with the new distributed social network called Mastodon (https://mastodon.technology/@gideonro). It's far from perfect, but one thing that is very different is that it is open source and federated, rather than centrally owned and controlled.

There are lots of implications to this different model. For one, there is lots of competition and innovation in the works because Mastodon sits on top of GNU Social and rests within a "Fediverse" of related, and interoperable, social network platforms. They are working on solutions that make it easy to export your content from one platform to another - to prevent lock-in. Also, there is a lot of visibility on exactly what investments are being made in the platform by various contributors.

More importantly though, there is a very conscious understanding that the value of these networks is only partially the result of the software developers behind these solutions. Just as much of it lies with the end users.

In the end, this is the thing that I am most frustrated about right now with Google+. End users have made this place every bit as much as the coders and product planners behind Google+. This isn't to in any way diminish the importance of those contributions. But what I do find frustrating is the way that Google seems to regularly dismiss the importance, and the real economic and social value, of end user contributions. This was true with Google Reader, and sadly it appears to be true with Google+.

I'm still rooting for Google+ to turn things around, of course. I have a huge soft spot for this place, given all the great learning I've done here with my fellow travelers. But one thing is clear: I'm losing my patience, and I don't think I'm alone. ___Bye-bye, Google+ — but what next?

Google+ is sliding downhill. A couple years ago my posts would garner comments from lots of smart people, leading to long and deep discussions. These days only a few stalwarts remain — a skeleton crew. I've copied most of my posts here to my website and blog. I mainly post here out of inertia: for certain purposes, I haven't found anything better yet.

As for the reasons, I agree with +Gideon Rosenblatt's analysis. Also read the many comments on his post! But the more important question is: what to do now?

Instead of whining about our masters, we should be our own masters — and unleash our creative energies! A bottom-up approach, run by all of us, could be better than top-down corporate control. A diverse, flexible federation could be better than a single unified platform.

Has anyone here tried Mastodon yet?

Mastodon is a free, open-source social network. A decentralized alternative to commercial platforms, it avoids the risks of a single company monopolizing your communication. Pick a server that you trust — whichever you choose, you can interact with everyone else. Anyone can run their own Mastodon instance and participate in the social network seamlessly.

You can check it out here:

https://mastodon.social/about

posted image

2017-04-18 16:24:01 (19 comments; 20 reshares; 81 +1s; )Open 

Biology as Information Dynamics

I'm giving a talk at the Stanford Complexity Group this Thursday afternoon, April 20th. If you're around - like in Silicon Valley - please drop by! It will be in Clark S361 at 4:20 pm.

Here's the idea. Everyone likes to say that biology is all about information. There's something true about this - just think about DNA. But what does this insight actually do for us? To figure it out, we need to do some work.

Biology is also about things that make copies of themselves. So it makes sense to figure out how information theory is connected to the 'replicator equation' — a simple model of population dynamics for self-replicating entities.

To see the connection, we need to use relative information: the information of one probability distribution relative to another, also known ast... more »

Biology as Information Dynamics

I'm giving a talk at the Stanford Complexity Group this Thursday afternoon, April 20th. If you're around - like in Silicon Valley - please drop by! It will be in Clark S361 at 4:20 pm.

Here's the idea. Everyone likes to say that biology is all about information. There's something true about this - just think about DNA. But what does this insight actually do for us? To figure it out, we need to do some work.

Biology is also about things that make copies of themselves. So it makes sense to figure out how information theory is connected to the 'replicator equation' — a simple model of population dynamics for self-replicating entities.

To see the connection, we need to use relative information: the information of one probability distribution relative to another, also known as the Kullback–Leibler divergence. Then everything pops into sharp focus.

It turns out that free energy — energy in forms that can actually be used, not just waste heat — is a special case of relative information Since the decrease of free energy is what drives chemical reactions, biochemistry is founded on relative information.

But there's a lot more to it than this! Using relative information we can also see evolution as a learning process, fix the problems with Fisher's fundamental theorem of natural selection, and more.

So this what I'll talk about! You can see slides of an old version here:

http://math.ucr.edu/home/baez/bio_asu/

but my Stanford talk will be videotaped and it'll eventually be here:

https://www.youtube.com/user/StanfordComplexity

You can already see lots of cool talks at this location!

#biology___

posted image

2017-04-10 15:47:53 (26 comments; 21 reshares; 65 +1s; )Open 

Rats!

Medical research using mice and rats tries to control all the variables - making everything the same. But it doesn't work...

... and maybe it's a bad idea in the first place! Joseph Garner at the Stanford University Medical Center has some ideas about this:

The philosophy behind mouse research has been to make everything as uniform as possible, so results from one facility would be the same as the identical experiment elsewhere.

But despite extensive efforts to be consistent, this setup hides a huge amount of variation. Bedding may differ from one facility to the next. So might the diet. Mice respond strongly to individual human handlers. Mice also react differently depending on whether their cage is up near the fluorescent lights or hidden down in the shadows.

Garner and colleagues tried to run identical experiments in six... more »

Rats!

Medical research using mice and rats tries to control all the variables - making everything the same. But it doesn't work...

... and maybe it's a bad idea in the first place! Joseph Garner at the Stanford University Medical Center has some ideas about this:

The philosophy behind mouse research has been to make everything as uniform as possible, so results from one facility would be the same as the identical experiment elsewhere.

But despite extensive efforts to be consistent, this setup hides a huge amount of variation. Bedding may differ from one facility to the next. So might the diet. Mice respond strongly to individual human handlers. Mice also react differently depending on whether their cage is up near the fluorescent lights or hidden down in the shadows.

Garner and colleagues tried to run identical experiments in six different mouse facilities, scattered throughout research centers in Europe. Even using genetically identical mice of the same age, the results varied all over the map.

Garner says scientists shouldn't even be trying to do experiments this way.

"Imagine you were doing a human drug trial and you said to the FDA, 'OK, I'm going to do this trial in 43-year-old white males in one small town in California,'" Garner says — a town where everyone lives in identical ranch homes, with the same monotonous diets and the same thermostat set to the same temperature.

"Which is too cold, and they can't change it," he goes on. "And oh, they all have the same grandfather!"

The FDA would laugh that off as an insane setup, Garner says.

"But that's exactly what we do in animals. We try to control everything we can possibly think of, and as a result we learn absolutely nothing."

Garner argues that research based on mice would be more reliable if it were set up more like experiments in humans — recognizing that variation is inevitable, and designing to embrace it rather than ignore it. He and his colleagues have recently published a manifesto, urging colleagues in the field to look at animals in this new light.

Here's the manifesto:

• Joseph P Garner, Brianna N Gaskill, Elin M Weber, Jamie Ahloy-Dallaire and Kathleen R Pritchett-Corning, Introducing therioepistemology: the study of how knowledge is gained from animal research. Available at http://www.labanimal.com/laban/journal/v46/n4/pdf/laban.1224.pdf

The quote is from the article I'm linking to - the whole thing is good.

#biology___

posted image

2017-04-08 16:23:36 (14 comments; 42 reshares; 132 +1s; )Open 

Making a new dog

Dogs are now considered to be the same species as wolves. They can interbreed with wolves just fine. They've just evolved to look and act different through interaction with us. They eat things wolves wouldn't touch. Dingoes, in Australia, are semi-wild dogs that went through a similar evolution.

Now that humans have taken over the world, there is very little true wilderness. In most places where wolves roam, they encounter people. They have the option of trying to get food from human sources. It's often easier than hunting.

This means that all wolves are evolving into something new. They're roaming less, getting less scared of people. We're "making a new dog".

That's what this paper is about:

• Thomas M. Newsome et al, Making a new dog?, BioScience 67 (2017), 374-381. A... more »

Making a new dog

Dogs are now considered to be the same species as wolves. They can interbreed with wolves just fine. They've just evolved to look and act different through interaction with us. They eat things wolves wouldn't touch. Dingoes, in Australia, are semi-wild dogs that went through a similar evolution.

Now that humans have taken over the world, there is very little true wilderness. In most places where wolves roam, they encounter people. They have the option of trying to get food from human sources. It's often easier than hunting.

This means that all wolves are evolving into something new. They're roaming less, getting less scared of people. We're "making a new dog".

That's what this paper is about:

• Thomas M. Newsome et al, Making a new dog?, BioScience 67 (2017), 374-381. Available at https://doi.org/10.1093/biosci/bix022.

And as humans encroach on their range, wolves are having more trouble finding mates. Sometimes they mate with domestic dogs. But mainly they're starting to interbreed with coyotes! This especially true in the northeast US. There are now zones where coyote populations are more wolf-like. They've got wolf genes affecting their body size and proportions.

So: nature is doing its thing. There is no sharp separation between nature and culture, civilization and wilderness. The rapid changes in human culture are rippling through the whole biosphere in a myriad of ways.

#biology___

posted image

2017-04-07 17:17:14 (6 comments; 7 reshares; 85 +1s; )Open 

Mysterious wave patterns in biology - demystified

The mathematician Gheorghe Craciun recently visited U.C. Riverside, and he told me something amazing. All the proteins in your body are made of peptides - strings of amino acids. Biologists have made big databases of peptides. If you graph how many peptides there are as a function of mass, you get the curves shown here.

The number of peptides generally grows as a function of mass, since there are more ways to string together a lot of amino acids than just a few. But the number also waves up and down! The waves are almost the same in human peptides, mouse peptides and yeast peptides.

What causes these waves?

Gheorghe Craciun and his colleague Shane Hubler figured it out. It turns out to be a math puzzle with a beautiful answer. Read the whole story at my blog:
... more »

Mysterious wave patterns in biology - demystified

The mathematician Gheorghe Craciun recently visited U.C. Riverside, and he told me something amazing. All the proteins in your body are made of peptides - strings of amino acids. Biologists have made big databases of peptides. If you graph how many peptides there are as a function of mass, you get the curves shown here.

The number of peptides generally grows as a function of mass, since there are more ways to string together a lot of amino acids than just a few. But the number also waves up and down! The waves are almost the same in human peptides, mouse peptides and yeast peptides.

What causes these waves?

Gheorghe Craciun and his colleague Shane Hubler figured it out. It turns out to be a math puzzle with a beautiful answer. Read the whole story at my blog:

https://johncarlosbaez.wordpress.com/2017/04/06/periodic-patterns-in-peptide-masses/

This is the puzzle: how many ways can you write the mass of a peptide as a sum of the masses of the 20 amino acids found in nature? (In this puzzle you have to keep track of the order of the masses you're adding up.)

This puzzle, while solved, leads to some other math puzzles that seem even more exciting to me. One of them - in the comments to my blog article - asks if the wavelength of these waves is a robust purely mathematical phenomenon. Does it depend a lot on the precise masses of the amino acids in nature, or there something pretty general going on here?

In other words: to what extent are the wave patterns in peptide masses built into the structure of pure math?

#biology___

posted image

2017-04-06 14:45:49 (11 comments; 10 reshares; 45 +1s; )Open 

Applied Category Theory

The American Mathematical Society is having a meeting here at U. C. Riverside during the weekend of November 4th and 5th, 2017. I’m organizing a session on Applied Category Theory, and I’m looking for people to give talks!

The goal is to start a conversation about applications of category theory, not within pure math or fundamental physics, but to other branches of science and engineering—especially those where the use of category theory is not already well-established. For example, my students and I have been applying category theory to chemistry, electrical engineering, control theory and Markov processes.

Alas, we have no funds for travel and lodging. If you’re interested in giving a talk, please submit an abstract here:

• General information about abstracts, American Mathematical Society,http://... more »

Applied Category Theory

The American Mathematical Society is having a meeting here at U. C. Riverside during the weekend of November 4th and 5th, 2017. I’m organizing a session on Applied Category Theory, and I’m looking for people to give talks!

The goal is to start a conversation about applications of category theory, not within pure math or fundamental physics, but to other branches of science and engineering—especially those where the use of category theory is not already well-established. For example, my students and I have been applying category theory to chemistry, electrical engineering, control theory and Markov processes.

Alas, we have no funds for travel and lodging. If you’re interested in giving a talk, please submit an abstract here:

• General information about abstracts, American Mathematical Society,
http://www.ams.org/meetings/abstracts/abstracts

More precisely, please read the information there and then click on the link on that page to submit an abstract. It should then magically fly through cyberspace to me! Abstracts are due September 12th, but the sooner you submit one, the greater the chance that we’ll have space.

For the program of the whole conference, go here:

• Fall Western Sectional Meeting, U. C. Riverside, Riverside, California, 4–5 November 2017, http://www.ams.org/meetings/sectional/2243_special.html

We’ll be having some interesting plenary talks:

• Paul Balmer, UCLA, An invitation to tensor-triangular geometry.

• Pavel Etingof, MIT, Double affine Hecke algebras and their applications.

• Monica Vazirani, U.C. Davis, Combinatorics, categorification, and crystals.___

posted image

2017-04-04 15:56:34 (16 comments; 6 reshares; 83 +1s; )Open 

Trillions of warriors, in a battle visible from space

See the murky cloud in the water? It's made of dying warriors - tiny sea creatures called coccolithophores who are fighting viruses, losing, dying and falling to the sea floor.

It's not an unusual event. It happens around the globe all the time. This war has been going on for millions of years. The combatants have evolved intricate strategies to outwit each other. And most interestingly, the way this battle plays out is crucial for all oxygen-breathing life on this planet.

Listen to the story here. You won't regret it! It's well-told, it's thrilling, and it will make you think of the world in a new way:

http://www.radiolab.org/story/190284-war-we-need/

#biology

Trillions of warriors, in a battle visible from space

See the murky cloud in the water? It's made of dying warriors - tiny sea creatures called coccolithophores who are fighting viruses, losing, dying and falling to the sea floor.

It's not an unusual event. It happens around the globe all the time. This war has been going on for millions of years. The combatants have evolved intricate strategies to outwit each other. And most interestingly, the way this battle plays out is crucial for all oxygen-breathing life on this planet.

Listen to the story here. You won't regret it! It's well-told, it's thrilling, and it will make you think of the world in a new way:

http://www.radiolab.org/story/190284-war-we-need/

#biology___

posted image

2017-04-02 16:33:11 (73 comments; 15 reshares; 77 +1s; )Open 

Spider-Ganesha

It's a natural combination. Ganesha is one of the most beloved of the Hindu gods. Kids love him, because after all, just how cool is an elephant-headed god? But he's also revered as the remover of obstacles, the patron of arts and sciences - and the god of beginnings, honored at the start of ceremonies. He first appeared around the 5th century AD, and he's been spreading ever since. Even many Buddhists and Jains like him.

Spider-Man is one of the most beloved of the Marvel Comics superheroes. He has super strength, extreme agility, a "spider-sense" for detecting foes, and the ability to cling to most surfaces and shoot spiderwebs using wrist-mounted devices of his own invention. And yet he's approachable, since he's also Peter Parker, a photographer at the Daily Bugle with problems like our own.

I don't know... more »

Spider-Ganesha

It's a natural combination. Ganesha is one of the most beloved of the Hindu gods. Kids love him, because after all, just how cool is an elephant-headed god? But he's also revered as the remover of obstacles, the patron of arts and sciences - and the god of beginnings, honored at the start of ceremonies. He first appeared around the 5th century AD, and he's been spreading ever since. Even many Buddhists and Jains like him.

Spider-Man is one of the most beloved of the Marvel Comics superheroes. He has super strength, extreme agility, a "spider-sense" for detecting foes, and the ability to cling to most surfaces and shoot spiderwebs using wrist-mounted devices of his own invention. And yet he's approachable, since he's also Peter Parker, a photographer at the Daily Bugle with problems like our own.

I don't know who invented Spider-Ganesha, and I don't know if this blend will catch on. But it could - the line between gods and superheroes is smaller than monotheists might think. They say that after his death Hercules ascended to Olympus. There was an Egyptian cult honoring Alexander the Great from the 3rd to the 1st centuries BC. And the historical Chinese general Guan Yu was deified about 300 years after his death. I've seen plenty of statues of him in Taoist and Buddhist temples in Shanghai and Singapore - and in Hong Kong, you can find him in every police station!

If we're going to have gods and heroes, I say we should have lots, and do it with a playful, relaxed attitude, enjoying them without "believing" in them.

So, three cheers for Spider-Ganesha!___

posted image

2017-04-01 16:32:43 (32 comments; 30 reshares; 130 +1s; )Open 

Message from Ramanujan

Last night, in a dream, Ramanujan showed me this formula. It expresses pi, or

π = 3.1415926535...

in terms of the golden ratio, or

Φ = 1.6180339887...

He said he'd been meaning to write down this formula just when he died. "An equation for me has no meaning unless it represents a thought of the goddess Mahalakshmi", he proclaimed - and then I woke up.

After his death, his brother Tirunarayanan compiled Ramanujan's remaining handwritten notes consisting of formulae on singular moduli, hypergeometric series and continued fractions - but I just checked, and this was not among them.

For the full true story, see:

https://johncarlosbaez.wordpress.com/2017/03/07/pi-and-the-golden-ratio/



Message from Ramanujan

Last night, in a dream, Ramanujan showed me this formula. It expresses pi, or

π = 3.1415926535...

in terms of the golden ratio, or

Φ = 1.6180339887...

He said he'd been meaning to write down this formula just when he died. "An equation for me has no meaning unless it represents a thought of the goddess Mahalakshmi", he proclaimed - and then I woke up.

After his death, his brother Tirunarayanan compiled Ramanujan's remaining handwritten notes consisting of formulae on singular moduli, hypergeometric series and continued fractions - but I just checked, and this was not among them.

For the full true story, see:

https://johncarlosbaez.wordpress.com/2017/03/07/pi-and-the-golden-ratio/

___

posted image

2017-03-31 15:25:03 (107 comments; 16 reshares; 179 +1s; )Open 

Donald Trump's plan to fight climate change

Here it is: stop saying the phrase "climate change". If you don't say "climate change", everything will be okay. So just ban the phrase "climate change". And while you're at it, deny there's a ban.

That's the plan, anyway. A director of the Office of International Climate and Clean Energy, part of the Department of Energy, has told staff to stop using the phrases "climate change," "emissions reduction" and "Paris Agreement" in written memos, briefings or other written communications. When asked about this, a spokeswoman said there is no ban.

Of course, even worse than this ban is Trump's executive order telling the Environmental Protection Agency to start unwinding Obama's Clean Power Plan. Over at the EPA, the truth about that ... more »

Donald Trump's plan to fight climate change

Here it is: stop saying the phrase "climate change". If you don't say "climate change", everything will be okay. So just ban the phrase "climate change". And while you're at it, deny there's a ban.

That's the plan, anyway. A director of the Office of International Climate and Clean Energy, part of the Department of Energy, has told staff to stop using the phrases "climate change," "emissions reduction" and "Paris Agreement" in written memos, briefings or other written communications. When asked about this, a spokeswoman said there is no ban.

Of course, even worse than this ban is Trump's executive order telling the Environmental Protection Agency to start unwinding Obama's Clean Power Plan. Over at the EPA, the truth about that leaked out for a day. They put this quote on their website:

Senator Shelly Moore Capito (W.Va)

With this Executive Order, President Trump has chosen to recklessly bury his head in the sand. Walking away from the Clean Power Plan and other climate initiatives, including critical resiliency projects is not just irresponsible— it's irrational. Today's executive order calls into question America's credibility and our commitment to tackling the greatest environmental challenge of our lifetime. With the world watching, President Trump and Administrator Pruitt have chosen to shirk our responsibility, disregard clear science and undo the significant progress our country has made to ensure we leave a better, more sustainable planet for generations to come.

Whoops! Actually another senator, Tom Carper of Delaware, said this.

Meawhile, Attorney General Eric T. Schneiderman of New York said he would challenge Trump's order, since it violates the Clean Air Act and established case law:

If they want to go back into the rule-making process, we believe they are compelled under law to come up with something close to the Clean Power Plan. They probably don’t want to hear this again, but if they want to repeal, they have to replace.

The ban:

http://www.politico.com/story/2017/03/energy-department-climate-change-phrases-banned-236655

The leaked truth:

http://www.motherjones.com/environment/2017/03/pruitts-epa-capito-carper-lol

Trump's executive order, and the reaction:

https://www.nytimes.com/2017/03/28/climate/trump-executive-order-climate-change.html

#climateaction___

posted image

2017-03-30 17:16:25 (10 comments; 9 reshares; 79 +1s; )Open 

Mock Modular Mathieu Moonshine Modules

That's the title of a far-out paper with six authors that tries to connect several topics.

The basic building blocks of symmetry are the simple groups: all other groups can be built from these. The finite simple groups have been completely classified, and there are various infinite series together with 26 exceptions called sporadic finite simple groups. The largest of these is the Monster, with almost 10^54 elements. Amazingly, this exotic entity is connected to something much simpler: the modular j-function, a function that describes the shape of tori. This shocking connection, called Monstrous Moonshine, has been explained using string theory: the j-function arises naturally from a string theory whose symmetry group is the Monster. But personally I feel we are just beginning to understand the... more »

Mock Modular Mathieu Moonshine Modules

That's the title of a far-out paper with six authors that tries to connect several topics.

The basic building blocks of symmetry are the simple groups: all other groups can be built from these. The finite simple groups have been completely classified, and there are various infinite series together with 26 exceptions called sporadic finite simple groups. The largest of these is the Monster, with almost 10^54 elements. Amazingly, this exotic entity is connected to something much simpler: the modular j-function, a function that describes the shape of tori. This shocking connection, called Monstrous Moonshine, has been explained using string theory: the j-function arises naturally from a string theory whose symmetry group is the Monster. But personally I feel we are just beginning to understand the connection. Experts see how the pieces fit together, but proving that they do requires big calculations, and why they fit together remains an utter mystery!

How do you solve a mystery like this? We really need good new ideas, but those are hard to summon on demand. So, one useful approach is to collect more data. It turns out that other sporadic finite simple groups are also connected to string theory! One of the first to be discovered is the Mathieu group M24. Now people are starting to see this group in string theory!

However, it's tricky. At first, nobody knew a string theory whose symmetry group is M24. Instead, they found string theories whose symmetry groups are various subgroups of M24. When you combine these subgroups, you can get all of M24. This was called symmetry surfing.

In particular, there's a kind of 4-dimensional space called a K3 surface. There are lots of them. We can set up string theories on different surfaces of this kind. Associated to these are various functions, relatives of the j-function called mock modular forms. The coefficients of these functions are connected to the group M24. Symmetry surfing provided an explanation: these different string theories have different subgroups of M24 as symmetries.

However, symmetry surfing is not truly satisfactory: it's like putting together a picture of a face from a collage of pieces. The new paper "Mock Modular Mathieu Moonshine Modules" goes further: it constructs a number of string theories whose symmetry group includes all of M24. But many questions remain unanswered.

In fact, the first mock modular forms were discovered by Ramanujan in a letter he sent to Hardy on January 12, 1920. Ramanujan had a strange ability to discover functions and equations that only became comprehensible to the rest of us after string theory was discovered. That's another mystery: how did he get so far ahead of his time?

For a nontechnical intro to these ideas, see:

• Natalie Wolchover, Moonshine master toys with string theory, Quanta Magazine, https://www.quantamagazine.org/20160804-miranda-cheng-moonshine-string-theory/

For the real thing, check out this:

• Miranda Cheng, Xi Dong, John Duncan, Sarah Harrison, Shamit Kachru and Timm Wrase, Mock modular Mathieu moonshine modules, available at https://arxiv.org/abs/1406.5502.

M24 is cool because it's connected to the magic powers of the number 24, which underlie a lot of stuff in string theory... but it's also within reach of ordinary mortals! It's the symmetry group of the Golay code - a set of 24-bit code words that can be gotten from deeply pondering this movie by Greg Egan.

You'll notice that this picture has 12 red balls and 12 green cylinders. When a green cylinder lights up, so do the red balls that don't touch it. Let's use a 1 to say that something is lit up and a 0 to say that it's not, and write down a list 24 zeros and ones to say which balls and cylinders are lit up. We get various 24-bit strings this way: 12, in fact. We get others by adding these mod 2. The set of all these 24-bit strings is called the Golay code.

If we look at all permutations of the 24 bits that send bit strings in the Golay code to bit strings in the Golay code, we get the group M24.

The Golay code is deeply connected to the Leech lattice and then the Monster group - but that's another story for another day.

#geometry
___

posted image

2017-03-27 16:14:42 (0 comments; 24 reshares; 154 +1s; )Open 

___

posted image

2017-03-26 22:11:47 (14 comments; 16 reshares; 91 +1s; )Open 

Desargues graph in 5 dimensions

This image by +Greg Egan shows various views of a 5-dimensional cube. Some vertices and edges are drawn in gray, while others are emphasized, showing the Desargues graph.

The vertices of a 5d cube can be seen as 5-bit strings, like this:

00101

There are 32 of theem The blue dots in Egan's image are strings with two 1's in them. The red dots are strings with three 1's. An edge lies in the Desargues graph - so Egan draws it as a dark line - if it goes from a bit string with two 1's to a bit string with all those 1's and one more.

The Desargues graph is beautifully symmetrical on its own, but it seems even more beautiful to me when it's sitting inside the 5d cube in this way.

Egan does an even fancier trick with the Desargues graph in another post. Instead of 5-bit... more »

Desargues graph in 5 dimensions

This image by +Greg Egan shows various views of a 5-dimensional cube. Some vertices and edges are drawn in gray, while others are emphasized, showing the Desargues graph.

The vertices of a 5d cube can be seen as 5-bit strings, like this:

00101

There are 32 of theem The blue dots in Egan's image are strings with two 1's in them. The red dots are strings with three 1's. An edge lies in the Desargues graph - so Egan draws it as a dark line - if it goes from a bit string with two 1's to a bit string with all those 1's and one more.

The Desargues graph is beautifully symmetrical on its own, but it seems even more beautiful to me when it's sitting inside the 5d cube in this way.

Egan does an even fancier trick with the Desargues graph in another post. Instead of 5-bit strings, he imagines pizzas with 5 possible toppings:

Desargues delivers drones

A fleet of twenty drones is sent out to deliver pizzas, with every possible choice of either two or three toppings from a menu of five.

Whenever two drones are carrying pizzas that differ by the addition of one extra topping, they must fly at a fixed distance from each other, and the precise distance depends on the particular topping that you would need to add to the two-topping pizza to make its cargo identical to its three-topping neighbour.

Can we have these drones flying loops around each other, without any of them colliding, even if they all fly at the same height?

Yes!

To see an animated gif of how it works, go here:

https://plus.google.com/u/0/113086553300459368002/posts/Qzb9JFUtr48

#geometry
___

posted image

2017-03-25 16:48:53 (9 comments; 14 reshares; 201 +1s; )Open 

The clouds of Jupiter

This photo was taken by the spacecraft called Juno, named after Jupiter's wife, who was able to see through the clouds that Jupiter created to hide his mischief.

Juno took this picture on February 2nd this year, 14,500 kilometers above the giant planet's cloud tops. It's a closeup of a dark spot, which in fact is a huge storm system.

One cool thing about the Juno mission is that it involves a lot of "citizen scientists", who get to vote on various decisions. One of them, Roman Tkachenko, helped enhance the color here to bring out the rich detail in the storm and surrounding clouds. Just south of the dark storm is a bright, oval-shaped storm with high, bright, white clouds, reminiscent of a swirling galaxy. I cut out the top part of this picture, because the bottom is very dark. The whole thing is here:
... more »

The clouds of Jupiter

This photo was taken by the spacecraft called Juno, named after Jupiter's wife, who was able to see through the clouds that Jupiter created to hide his mischief.

Juno took this picture on February 2nd this year, 14,500 kilometers above the giant planet's cloud tops. It's a closeup of a dark spot, which in fact is a huge storm system.

One cool thing about the Juno mission is that it involves a lot of "citizen scientists", who get to vote on various decisions. One of them, Roman Tkachenko, helped enhance the color here to bring out the rich detail in the storm and surrounding clouds. Just south of the dark storm is a bright, oval-shaped storm with high, bright, white clouds, reminiscent of a swirling galaxy. I cut out the top part of this picture, because the bottom is very dark. The whole thing is here:

https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA21386

I'm a bit confused about how much the Juno mission was damaged by the problem that happened last October:

For NASA's Juno spacecraft, all had been going well since its July 4th insertion into orbit around Jupiter—as well as things can go when radiation is slowly eating away at a spacecraft, that is. That ended when mission managers tried to send a command to the robotic probe on Thursday.

According to a NASA news release, two helium check valves that play an important role in the firing of the spacecraft's main engine did not operate properly during the command sequence. "The valves should have opened in a few seconds, but it took several minutes," Rick Nybakken, Juno project manager at NASA's Jet Propulsion Laboratory, said. "We need to better understand this issue before moving forward with a burn of the main engine."

NASA had intended to fire the spacecraft's Leros 1b engine, its primary source of thrust, next Wednesday. The goal was to bring Juno into a shorter orbital period around the gas giant, from 53.4 to 14 days. The optimal time for such a "period reduction maneuver" is when the spacecraft is closest to the planet, so Juno's next opportunity for this engine burn will not come until Dec. 11. This was to be the final burn of the Leros 1b engine, which fired perfectly on July 4 to put Juno into a precise orbit around Jupiter. Future maneuvers can be conducted by smaller onboard thrusters.

Mission scientists emphasized that the longer orbital period would not affect the quality of science that Juno can collect as it flies close to the planet's poles. However, if the issue cannot be resolved, the spacecraft will not be able to make as many flybys as scientists hoped due to expected degradation of the spacecraft and its scientific instruments as it flies through Jupiter's harsh radiation environment. NASA hoped Juno would make 36 orbits during the next 20 months.

This was a summary by Eric Berger, senior space editor at Ars Technica, last October:

https://arstechnica.com/science/2016/10/nasas-juno-spacecraft-has-a-problem-with-its-engine/

I haven't paid enough attention since then to know the full story!

#astronomy___

posted image

2017-03-19 15:33:14 (61 comments; 15 reshares; 118 +1s; )Open 

Everything is fine again

I've stopped worrying about Trump. I'm taking Impeachara! 

Everything is fine again

I've stopped worrying about Trump. I'm taking Impeachara! ___

posted image

2017-03-12 18:26:46 (25 comments; 10 reshares; 65 +1s; )Open 

Restoring the North Cascades Ecosystem

In two days, the National Park Service will decide whether to reintroduce grizzly bears into the North Cascades near Seattle. If you leave a comment on their website, you can help make this happen! Follow the easy directions here:

http://theoatmeal.com/blog/grizzlies_north_cascades

Please go ahead! Then reshare. This can be your good deed for the day.

But if you're curious:

Grizzly bears are traditionally the top predator in the North Cascades. Without the top predator, the whole ecosystem is thrown out of balance. I know this from my childhood in northern Virginia, where deer are stripping the forest of all low-hanging greenery with no wolves to control them. With the top predator, the whole ecosystem springs to life and starts humming like a well-tuned engine!

There are... more »

Restoring the North Cascades Ecosystem

In two days, the National Park Service will decide whether to reintroduce grizzly bears into the North Cascades near Seattle. If you leave a comment on their website, you can help make this happen! Follow the easy directions here:

http://theoatmeal.com/blog/grizzlies_north_cascades

Please go ahead! Then reshare. This can be your good deed for the day.

But if you're curious:

Grizzly bears are traditionally the top predator in the North Cascades. Without the top predator, the whole ecosystem is thrown out of balance. I know this from my childhood in northern Virginia, where deer are stripping the forest of all low-hanging greenery with no wolves to control them. With the top predator, the whole ecosystem springs to life and starts humming like a well-tuned engine!

There are several plans to restore grizzlies to the North Cascades. On the link, Matthew Inman supports Alternative C — Incremental Restoration. I'm not an expert on this issue, so I went ahead and supported that. There are actually 4 alternatives on the table:

Alternative A — No Action. They'll keep doing what they're already doing. The few grizzlies already there would be protected from poaching, the local population would be advised on how to deal with grizzlies, and the bears would be monitored. All other alternatives will do this and more.

Alternative B — Ecosystem Evaluation Restoration. Up to 10 grizzly bears will be captured from source populations in northwestern Montana and/or south-central British Columbia and released at a single remote site on Forest Service lands in the North Cascades. This will take 2 years, and then they'll be monitored for 2 years before deciding what to do next.

Alternative C — Incremental Restoration. 5 to 7 grizzly bears will be captured and released into the North Casades each year over roughly 5 to 10 years, with a goal of establishing an initial population of 25 grizzly bears. Bears would be released at multiple remote sites. They can be relocated or removed if they cause trouble. Alternative C is expected to reach the restoration goal of approximately 200 grizzly bears within 60 to 100 years.

Alternative D — Expedited Restoration. 5 to 7 grizzly bears will be captured and released into the North Casades each year until the population reaches about 200, which is what the area can easily support.

So, pick your own alternative if you like!

By the way, the remaining grizzly bears in the western United States live within six recovery zones:

the Greater Yellowstone Ecosystem (GYE) in Wyoming and southwest Montana;

the Northern Continental Divide Ecosystem (NCDE) in northwest Montana;

the Cabinet-Yaak Ecosystem (CYE) in extreme northwestern Montana and the northern Idaho panhandle;

the Selkirk Ecosystem (SE) in northern Idaho and northeastern Washington;

the Bitterroot Ecosystem (BE) in central Idaho and western Montana;

and the North Cascades Ecosystem (NCE) in northwestern and north-central Washington.

For more:

• Draft Grizzly Bear Restoration Plan / Environmental Impact Statement: North Cascades Ecosystem, https://tinyurl.com/cascade-grizzlies

The picture is from this article:

http://www.seattletimes.com/pacific-nw-magazine/returning-grizzlies-to-the-north-cascades-is-the-right-thing-to-do/

If you're worried about reintroducing grizzly bears, read it!

#savingtheplanet
___

posted image

2017-03-11 06:57:28 (9 comments; 1 reshares; 15 +1s; )Open 

We the People

A Tribe Called Quest has a song for today's America. It's very catchy! The refrain is the distilled rhetoric of our dear leader:

All you black folks, you must go
All you Mexicans, you must go
And all you poor folks, you must go
Muslims and gays, boy we hate your ways

... refuted hilariously thus:

When we get hungry we eat the same fucking food: the ramen noodle.

For a version with lyrics, go here:

https://www.youtube.com/watch?v=eAoqWu6wmfI

I hear the drum beat is a sample from Black Sabbath's 'Behind The Wall Of Sleep'. Is that right?


We the People

A Tribe Called Quest has a song for today's America. It's very catchy! The refrain is the distilled rhetoric of our dear leader:

All you black folks, you must go
All you Mexicans, you must go
And all you poor folks, you must go
Muslims and gays, boy we hate your ways

... refuted hilariously thus:

When we get hungry we eat the same fucking food: the ramen noodle.

For a version with lyrics, go here:

https://www.youtube.com/watch?v=eAoqWu6wmfI

I hear the drum beat is a sample from Black Sabbath's 'Behind The Wall Of Sleep'. Is that right?
___

posted image

2017-03-10 23:18:16 (60 comments; 13 reshares; 110 +1s; )Open 

When light kisses darkness

This is one of many beautiful images on Thomas Baruchel's blog. They depict functions on the complex plane. Some are exquisitely baroque. This one is delightfully simple: a circle of light intersecting a larger circle of darkness. Its intense contrast reminds me of a solar eclipse.

The function here, like most on the blog, is defined by a continued fraction:

z exp(2πi / 3) / (z + (z exp(4πi / 3) / (z/2 + (z exp(6πi / 3) / (z/3 + ....

He says that "white parts on the picture are real values; black parts are imaginary ones." That doesn't fully explain how the numbers get turned into shades of gray. It would be nice to know the exact recipe. A more obvious choice would be to use the color wheel to describe the phase of a complex number and brightness or intensity to describe its absolute value. Butth... more »

When light kisses darkness

This is one of many beautiful images on Thomas Baruchel's blog. They depict functions on the complex plane. Some are exquisitely baroque. This one is delightfully simple: a circle of light intersecting a larger circle of darkness. Its intense contrast reminds me of a solar eclipse.

The function here, like most on the blog, is defined by a continued fraction:

z exp(2πi / 3) / (z + (z exp(4πi / 3) / (z/2 + (z exp(6πi / 3) / (z/3 + ....

He says that "white parts on the picture are real values; black parts are imaginary ones." That doesn't fully explain how the numbers get turned into shades of gray. It would be nice to know the exact recipe. A more obvious choice would be to use the color wheel to describe the phase of a complex number and brightness or intensity to describe its absolute value. But the simplicity of a grayscale image pays off in a kind of classic beauty.

Here's the image on Baruchel's blog:

https://kettenreihen.wordpress.com/2017/03/06/146/

It's number 146 of a long series. He has threatened to produce three a day - and so far he seems to be keeping up!

#geometry___

posted image

2017-03-09 16:31:23 (1 comments; 24 reshares; 95 +1s; )Open 

Madness

When you elect a crazy and corrupt president, he will surround himself with similar people - who will then do the same. Things will not go well.

Arctic sea is at record lows for this time of year. Last year was the hottest since records have been kept. Right now, high winds and drought are causing huge fires in the Midwest US. 22 million people are under threat! On Tuesday, tornadoes struck Minnesota - the earliest ever. That's right: tornadoes in early March in a northern state.

Scientists know why: the amount of carbon dioxide in the air has increased 25% since 1960. But Scott Pruitt, head of Trump's Environmental Protection Agency, is pretending not to comprehend. Speaking from a conference of his oil industry pals, he said:

“I think that measuring with precision human activity on the climate is something very challenging tod... more »

Madness

When you elect a crazy and corrupt president, he will surround himself with similar people - who will then do the same. Things will not go well.

Arctic sea is at record lows for this time of year. Last year was the hottest since records have been kept. Right now, high winds and drought are causing huge fires in the Midwest US. 22 million people are under threat! On Tuesday, tornadoes struck Minnesota - the earliest ever. That's right: tornadoes in early March in a northern state.

Scientists know why: the amount of carbon dioxide in the air has increased 25% since 1960. But Scott Pruitt, head of Trump's Environmental Protection Agency, is pretending not to comprehend. Speaking from a conference of his oil industry pals, he said:

“I think that measuring with precision human activity on the climate is something very challenging to do and there’s tremendous disagreement about the degree of impact. So no, I would not agree that it’s a primary contributor to the global warming that we see. But we don’t know that yet ... we need to continue the debate and continue the review and the analysis.

Worse still, Pruitt is intent on populating the EPA with people as reckless and corrupt as himself:

Mr. Pruitt, a former Oklahoma attorney general who built a career out of suing the agency he now leads, has moved to stock the top offices of the agency with like-minded conservatives — many of them skeptics of climate change and all of them intent on rolling back environmental regulations that they see as overly intrusive and harmful to business.

Mr. Pruitt has drawn heavily from the staff of his friend and fellow Oklahoma Republican, Senator James Inhofe, long known as Congress’s most prominent skeptic of climate science. A former Inhofe chief of staff, Ryan Jackson, will be Mr. Pruitt’s chief of staff. Another former Inhofe staff member, Byron Brown, will serve as Mr. Jackson’s deputy. Andrew Wheeler, a fossil fuel lobbyist and a former Inhofe chief of staff, is a finalist to be Mr. Pruitt’s deputy, although he requires confirmation to the position by the Senate.

To friends and critics, Mr. Pruitt seems intent on building an E.P.A. leadership that is fundamentally at odds with the career officials, scientists and employees who carry out the agency’s missions. That might be a recipe for strife and gridlock at the federal agency tasked to keep safe the nation’s clean air and water while safeguarding the planet’s future.

“He’s the most different kind of E.P.A. administrator that’s ever been,” said Steve J. Milloy, a member of the E.P.A. transition team who runs the website JunkScience.com, which aims to debunk climate change. “He’s not coming in thinking E.P.A. is the greatest thing since sliced bread. Quite the opposite.”

Gina McCarthy, who headed the E.P.A. under former President Barack Obama, said she too saw Mr. Pruitt as unique. “It’s fine to have differing opinions on how to meet the mission of the agency. Many Republican administrators have had that,” she said. “But here, for the first time, I see someone who has no commitment to the mission of the agency.”

A pair of Trump campaigners from Washington State are also heading into senior positions at the E.P.A. Don Benton, a former Washington state senator who headed President Trump’s state campaign, will be the agency’s senior liaison with the White House. Douglas Ericksen, a current Washington state senator, is being considered as the regional administrator of the E.P.A.’s Pacific Northwest office.

As a state senator, Mr. Ericksen has been active in opposing efforts to pass a state-level climate change law taxing carbon pollution. Last month, he invited Tony Heller, a climate denialist who blogs under the pseudonym Steven Goddard, to address a Washington State Senate committee on the costs of climate change policy. Mr. Heller’s blog says “global warming is the biggest fraud in science history.”

People can fool other people. They can even fool themselves. But they can't fool the laws of physics. We will all pay the price for this madness.

Please do something. At the very least, join me in contributing to the Sierra Club, the Environmental Defense Fund and other organizations who will sue the pants off this gang of crazies:

http://www.sierraclub.org/
https://www.edf.org/

#climateaction___

posted image

2017-03-09 08:00:45 (0 comments; 27 reshares; 59 +1s; )Open 

Join the resistance

When you see a drunk speeding down the road at night, his car weaving erratically across lanes, the question is not whether something terrible will happen. It's when. Same with President Trump. His increasingly crazy behavior is bound to get us in serious trouble. We have to be ready to do the right thing.

So this Saturday, I'm going to join 30 people at a local meeting of the American Civil Liberties Union, for "resistance training". They're happening all across the country! Find the one nearest you, and go there - Saturday March 11th.

The ACLU will continue to challenge President Trump’s unconstitutional actions in court and with PeoplePower.org, we will take that fight to the streets. We are in the fight of our lives right now, and what we have learned since Donald Trump’s inauguration is that there is agro... more »

Join the resistance

When you see a drunk speeding down the road at night, his car weaving erratically across lanes, the question is not whether something terrible will happen. It's when. Same with President Trump. His increasingly crazy behavior is bound to get us in serious trouble. We have to be ready to do the right thing.

So this Saturday, I'm going to join 30 people at a local meeting of the American Civil Liberties Union, for "resistance training". They're happening all across the country! Find the one nearest you, and go there - Saturday March 11th.

The ACLU will continue to challenge President Trump’s unconstitutional actions in court and with PeoplePower.org, we will take that fight to the streets. We are in the fight of our lives right now, and what we have learned since Donald Trump’s inauguration is that there is a growing army of people out there who want to be asked to do something big and important in response. We intend to activate these people to defend our Constitution, our shared American values and our future.

So says the director of the ACLU, Anthony Romero. This organization has seen a flood of donations and new members. According to the Associated Press:

The nearly century-old American Civil Liberties Union says it is suddenly awash in donations and new members as it does battle with President Donald Trump over the extent of his constitutional authority, with nearly $80 million in online contributions alone pouring in since the election.

That includes a record $24 million surge over two days after Trump banned people from seven predominantly Muslim countries from entering the United States. The organization said its membership has more than doubled since the election to a record of nearly 1.2 million, and its Twitter following has tripled.

The antibodies have been activated.___

posted image

2017-03-04 22:20:38 (54 comments; 34 reshares; 139 +1s; )Open 

Environmental Destruction

Republicans in Congress have cut the Environmental Protection Agency's budget by 20% since 2011. Now the Trump gang wants to cut its budget by another 25%.

To do this, they want to slash state grants by 30%. They want to cut the agency’s workforce by 20%. And most importantly, they want to zero out — that is, completely kill — almost two dozen programs, including the US government's main plan to fight climate change: the Clean Power Plan.

The EPA's new head, Scott Pruitt, actually led 14 lawsuits against the EPA. He worked hand-in-hand with fossil fuel companies to do this. Recently a judge forced him to reveal 7500 pages of documents proving it! Unfortunately — but not by coincidence — they came out a few days after Pruitt was hastily confirmed by the Senate.

For example:
The ema... more »

Environmental Destruction

Republicans in Congress have cut the Environmental Protection Agency's budget by 20% since 2011. Now the Trump gang wants to cut its budget by another 25%.

To do this, they want to slash state grants by 30%. They want to cut the agency’s workforce by 20%. And most importantly, they want to zero out — that is, completely kill — almost two dozen programs, including the US government's main plan to fight climate change: the Clean Power Plan.

The EPA's new head, Scott Pruitt, actually led 14 lawsuits against the EPA. He worked hand-in-hand with fossil fuel companies to do this. Recently a judge forced him to reveal 7500 pages of documents proving it! Unfortunately — but not by coincidence — they came out a few days after Pruitt was hastily confirmed by the Senate.

For example:

The emails highlight an often-chummy relationship between Pruitt’s office and Devon Energy, a major oil and gas exploration and production company based in Oklahoma City. The correspondence makes clear that top officials at the company met often with Pruitt or people who worked for him. Devon representatives also helped draft — and redraft — letters for Pruitt to sign and send to federal officials in an effort to stave off new regulations.

So, Pruitt is no friend of the agency he now runs. But either the budget cuts go beyond what Pruitt wants, or he's playing a clever "good cop, bad cop" routine to make EPA staffers hate him less. He claims he'll actually fight some of the budget cuts - though not the elimination of the Clean Power Plan.

But such assurances are doing little to address EPA staff concerns and sagging morale across the agency. One EPA staffer said recently that “it's as bad as you are hearing: The entire agency is under lockdown, the website . . . can't be updated. All reports, findings, permits and studies are frozen and not to be released. No presentations or meetings with outside groups are to be scheduled.”

“We are still doing our work, writing reports, doing cancer modeling for pesticides, hoping that this is temporary and we will be able to serve the public soon. But many of us are worried about an ideologically-fueled purging,” the source said.

The main hope for resistance now lies in Congress, where even some Republicans oppose the cuts to popular programs that clean up toxic waste, cut diesel emissions, and more:

Sen. Debbie Stabenow (D-MI), for example, warned in a statement that administration plans to cut funds for EPA's Great Lakes Initiative by 97 percent would undercut cleanups and other environmental programs in the region.

“This initiative has been critical to cleaning up our Great Lakes and waterways, restoring fish and wildlife habitats, and fighting invasive species,” she said in a statement. “Our Great Lakes are part of our DNA and an important driver of our economy in Michigan and I call on President Trump to reverse course on these harmful decisions.”

Even before details of the budget plan leaked, a bipartisan group of lawmakers from Chesapeake Bay states wrote to President Donald Trump urging him to fund EPA's Bay cleanup program at its current level of $73 million in FY18, though the administration plan would cut the program's funds by 93 percent.

“Through [EPA's] Chesapeake Bay Program, the Chesapeake Bay's health is improving significantly. . . . We must ensure that this important work continues and that federal funds continue to be available to support this effort,” the lawmakers said in their Feb. 23 letter.

Among those signing the letter were Reps. Robert Wittman (R-VA), Bobby Scott (D-VA), Andy Harris (R-MD), John Sarbanes (D-MD), Steny Hoyer (D-MD), Scott Taylor (R-VA), John Faso (R-NY), Barbara Comstock (R-VA) and others.

The Trump gang also plans to cut funds for the Chesapeake Bay and Puget Sound cleanup projects by 93%, and completely eliminate the San Francisco Bay cleanup project.

The first quote, about Pruitt working with oil and gas companies, comes from here:

• Brady Dennis and Steven Mufson, Thousands of emails detail EPA head’s close ties to fossil fuel industry, Washington Post, 22 February 2017, https://www.washingtonpost.com/news/energy-environment/wp/2017/02/22/oklahoma-attorney-generals-office-releases-7500-pages-of-emails-between-scott-pruitt-and-fossil-fuel-industry/

The second quote is from here:

• Anthony Lacey, EPA Staff brace for lengthy fight against massive proposed budget cuts, InsideEPA.com, 3 March 2017, https://insideepa.com/daily-news/epa-staff-brace-lengthy-fight-against-massive-proposed-budget-cuts

which you can read if you get a free trial subscription. Similarly for the third quote, which is from here:

• Maria Hegstad, Administration plan to slash EPA's budget faces broad opposition, InsideEPA.com, 3 March 2017, https://insideepa.com/daily-news/administration-plan-slash-epas-budget-faces-broad-opposition

#climateaction___

posted image

2017-03-04 16:42:09 (2 comments; 13 reshares; 90 +1s; )Open 

Add +Greg Egan to your circles if you enjoy stuff like this.

#geometry

Quasiperiodic tiling from recursion

The image below was made by taking three shapes — a regular decagon, and two kinds of hexagons (one of them resembling a bow-tie) — and using a set of substitution rules in which each shape is dissected into smaller copies of the same three shapes.

Quasiperiodic tilings were only discovered in Western mathematics with the work of Roger Penrose in the 1970s, but this recursive construction (albeit with only a single level of recursion) is believed to underly some of the patterns of tiles found in a number of medieval Islamic buildings.

“Girih”, the Persian word for “knot”, is used to describe the interwoven, braid-like patterns of strapwork that decorate these and other tilings when they are used in Islamic architecture.

Reference: “Decagonal and Quasi-crystalline Tilings in Medieval Islamic Architecture” by Peter J. Lu and Paul J. Steinhardt, Science 315, 1106 (2007).

http://www.peterlu.org/sites/peterlu.org/files/Science_315_1106_2007.pdf___Add +Greg Egan to your circles if you enjoy stuff like this.

#geometry

posted image

2017-03-02 23:51:12 (30 comments; 16 reshares; 74 +1s; )Open 

Squaring the circle with fractals

Take a 2 × 2 square and divide it into four squares.

Divide each of these four squares into 9 smaller squares, and remove the middle one.

Divide each smaller square into 25 even smaller squares, and remove the middle one.

Divide each even smaller square into 49 tiny squares, and remove the middle one.

Go on forever. When you're done, what's left has area equal to π, just like a circle of radius 1!

The picture here is by Ed Pegg. The math behind this fact is an old formula:

(8/9) × (24/25) × (48/49) × (80/81) × (120/121) × ... = π/4

John Wallis figured this out in 1655:

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

More interestingly, a similar fact is true 3 dimensions:

http://community.wolfram.com/groups/-/m/t/822984
more »

Squaring the circle with fractals

Take a 2 × 2 square and divide it into four squares.

Divide each of these four squares into 9 smaller squares, and remove the middle one.

Divide each smaller square into 25 even smaller squares, and remove the middle one.

Divide each even smaller square into 49 tiny squares, and remove the middle one.

Go on forever. When you're done, what's left has area equal to π, just like a circle of radius 1!

The picture here is by Ed Pegg. The math behind this fact is an old formula:

(8/9) × (24/25) × (48/49) × (80/81) × (120/121) × ... = π/4

John Wallis figured this out in 1655:

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

More interestingly, a similar fact is true 3 dimensions:

http://community.wolfram.com/groups/-/m/t/822984

and also in higher dimensions:

http://forums.xkcd.com/viewtopic.php?t=114760

Or check out this video:

https://www.youtube.com/watch?v=8pj8_zjelDo

#geometry___

posted image

2017-02-27 01:57:06 (29 comments; 14 reshares; 111 +1s; )Open 

The dark cloud

Ever since Trump became president he has cast a dark cloud over our country, poisoning the atmosphere, sucking us into the vortex of his madness. I'm sure many of you feel it. Andrew Sullivan explains it well:

I think this is a fundamental reason why so many of us have been so unsettled, anxious, and near panic these past few months. It is not so much this president’s agenda. That always changes from administration to administration. It is that when the linchpin of an entire country is literally delusional, clinically deceptive, and responds to any attempt to correct the record with rage and vengeance, everyone is always on edge.

There is no anchor any more. At the core of the administration of the most powerful country on earth, there is, instead, madness.

With someone like this barging into your consciousness every hour of everyd... more »

The dark cloud

Ever since Trump became president he has cast a dark cloud over our country, poisoning the atmosphere, sucking us into the vortex of his madness. I'm sure many of you feel it. Andrew Sullivan explains it well:

I think this is a fundamental reason why so many of us have been so unsettled, anxious, and near panic these past few months. It is not so much this president’s agenda. That always changes from administration to administration. It is that when the linchpin of an entire country is literally delusional, clinically deceptive, and responds to any attempt to correct the record with rage and vengeance, everyone is always on edge.

There is no anchor any more. At the core of the administration of the most powerful country on earth, there is, instead, madness.

With someone like this barging into your consciousness every hour of every day, you begin to get a glimpse of what it must be like to live in an autocracy of some kind. Every day in countries unfortunate enough to be ruled by a lone dictator, people are constantly subjected to the Supreme Leader’s presence, in their homes, in their workplaces, as they walk down the street. Big Brother never leaves you alone. His face bears down on you on every flickering screen. He begins to permeate your psyche and soul; he dominates every news cycle and issues pronouncements — each one shocking and destabilizing — round the clock. He delights in constantly provoking and surprising you, so that his monstrous ego can be perennially fed. And because he is also mentally unstable, forever lashing out in manic spasms of pain and anger, you live each day with some measure of trepidation. What will he come out with next? Somehow, he is never in control of himself and yet he is always in control of you.

One of the great achievements of free society in a stable democracy is that many people, for much of the time, need not think about politics at all. The president of a free country may dominate the news cycle many days — but he is not omnipresent — and because we live under the rule of law, we can afford to turn the news off at times. A free society means being free of those who rule over you — to do the things you care about, your passions, your pastimes, your loves — to exult in that blessed space where politics doesn’t intervene. In that sense, it seems to me, we already live in a country with markedly less freedom than we did a month ago. It’s less like living in a democracy than being a child trapped in a house where there is an abusive and unpredictable father, who will brook no reason, respect no counter-argument, admit no error, and always, always up the ante until catastrophe inevitably strikes. This is what I mean by the idea that we are living through an emergency.

This is why I can no longer enjoy blogging about math and science. I still enjoy thinking about them, and working on them. Indeed, they make an excellent escape from the nasty mess we're in. But to blog about them publicly feels like pretending in front of a crowd that life is normal, when in fact everything has gone terribly wrong.

Later this spring I will go to Hong Kong for a month. I'll be talking to Guowu Meng about Jordan algebras and physics. First I'll spend two weeks at the Sha Tin Hyatt, which is near the lively part of town; then I'll get housing near the Hong Kong University of Science and Technology, which is up north, in the boondocks.

I wonder how I will feel there. Of course that city-state has dire problems of its own, but in some important sense they will not be my problems. Even with its problems, Hong Kong is a lively and invigorating place — much more so than my usual summer hangout, Singapore. But here's what I don't know: will physical distance from the USA make me feel any more removed from the insanity there — any more at peace?

For now: help the ACLU by signing this petition! Over 300,000 people have so far, and I just did:

Do not delay – release all documents pertaining to Donald Trump’s actual or potential conflicts of interest. Trump has kept the American people in the dark for too long. For the sake of our democracy, we need you to bring this matter into the light and give the public access to this vital information.

https://action.aclu.org/secure/trumpFOIA

Andrew Sullivan's essay is here:

http://nymag.com/daily/intelligencer/2017/02/andrew-sullivan-the-madness-of-king-donald.html___

posted image

2017-02-23 22:04:34 (57 comments; 8 reshares; 55 +1s; )Open 

If the Earth were a doughnut

The famous philosopher Charles Saunders Peirce worked for a while at the U. S. Coast and Geodetic Survey. He invented a new map of the Earth. First you map the spherical Earth to a torus. Then you slice open the torus and unroll it to a square. You get this:

https://tinyurl.com/quincuncial-1

It's called Peirce's quincuncial.

Puzzle: why is it called that?

If you then make wallpaper with such squares, you get a cool infinite repeating map of the Earth, shown here:

https://tinyurl.com/quincuncial-2

These pictures are by Carlos A. Furuti.

But +Greg Egan did something cooler. He made an animation of the torus, showing how the continents move on it as the spherical Earth turns!

The math here is the math of elliptic functions. I explained it... more »

As the world turns, but the map stays still

The animation below was suggested by Michael Hardy, whose question on MathOverflow about the properties of a 2-to-1, almost-everywhere-conformal map from the torus to the sphere got me interested in the subject.

In a previous post, I showed a fixed mapping of two copies of the surface of the Earth onto a torus, and then rotated the resulting torus to reveal more of its surface than can be seen in any one fixed view.

But in this animation, while the torus itself stays fixed, the Earth rotates around its axis relative to the coordinate system used for the mapping.

The result makes it clear just how strange things are at some points on this map (in the previous view, the strangeness was deliberately hidden in the ocean). There are four branch points on the torus; if you walk around these points, the version of you mapped to the Earth will complete two circles around the corresponding point. You can only see two of the branch points in this view, but the positions of the other two are easy to imagine from the symmetry.

[Edited to add] Another version of this image (with a grid of longitude and latitude marked, and twice as many frames to give a smoother rotation – the file is about 17 Mb):

http://www.gregegan.net/images/tw4.gif

My previous post on the torus map:

https://plus.google.com/113086553300459368002/posts/8XXBvq9hjoK

Michael Hardy's question on MathOverflow:

http://mathoverflow.net/questions/260202/jacobis-elliptic-functions-and-plane-sections-of-a-torus

+Henry Segerman's interactive 3D model (which uses essentially the same map, but orients the Earth differently relative to the torus):

https://skfb.ly/MYpC

___If the Earth were a doughnut

The famous philosopher Charles Saunders Peirce worked for a while at the U. S. Coast and Geodetic Survey. He invented a new map of the Earth. First you map the spherical Earth to a torus. Then you slice open the torus and unroll it to a square. You get this:

https://tinyurl.com/quincuncial-1

It's called Peirce's quincuncial.

Puzzle: why is it called that?

If you then make wallpaper with such squares, you get a cool infinite repeating map of the Earth, shown here:

https://tinyurl.com/quincuncial-2

These pictures are by Carlos A. Furuti.

But +Greg Egan did something cooler. He made an animation of the torus, showing how the continents move on it as the spherical Earth turns!

The math here is the math of elliptic functions. I explained it here:

http://math.ucr.edu/home/baez/week229.html

posted image

2017-02-19 18:14:20 (8 comments; 13 reshares; 92 +1s; )Open 

Thank you!

The Azimuth Climate Data Backup Project is backing up 40 terabytes of US government climate data and copying it to a number of locations, to protect it from all possible threats:

http://math.ucr.edu/home/baez/azimuth_backup_project/

It's going well! Our Kickstarter campaign ended on January 31st and the money has recently reached us. Our original goal was $5000. We got $20,427 of donations, and after Kickstarter took its cut we received $18,590.96.

Soon I’ll tell you what our project has actually been doing — lots of good news. This time I just want to give a huge “thank you!” to all 627 people who contributed money on Kickstarter... many from here on Google+.

I recently sent out thank you notes to everyone, updating them on our progress and asking if they wanted their names listed. The blanks in the following listreprese... more »

Thank you!

The Azimuth Climate Data Backup Project is backing up 40 terabytes of US government climate data and copying it to a number of locations, to protect it from all possible threats:

http://math.ucr.edu/home/baez/azimuth_backup_project/

It's going well! Our Kickstarter campaign ended on January 31st and the money has recently reached us. Our original goal was $5000. We got $20,427 of donations, and after Kickstarter took its cut we received $18,590.96.

Soon I’ll tell you what our project has actually been doing — lots of good news. This time I just want to give a huge “thank you!” to all 627 people who contributed money on Kickstarter... many from here on Google+.

I recently sent out thank you notes to everyone, updating them on our progress and asking if they wanted their names listed. The blanks in the following list represent people who either didn’t reply, didn’t want their names listed, or backed out and decided not to give money. I’ll list people in chronological order: first contributors first.

Only 12 people backed out; the vast majority of blanks on this list are people who haven’t replied to my email. I noticed some interesting but obvious patterns. For example, people who contributed later are less likely to have answered my email. People who contributed more money were more likely to answer my email.

The magnitude of contributions ranged from $2000 to $1. A few of you offered to help in other ways. The response was international — this was really heartwarming! People from the US were more likely than others to ask not to be listed.

But instead of continuing to list statistical patterns, let me just thank everyone who contributed. Here's the list! (I’ll keep updating this list on the Azimuth blog, but not here.)

Daniel Estrada
Ahmed Amer
Saeed Masroor
Jodi Kaplan
John Wehrle
Bob Calder
Andrea Borgia
L Gardner

Uche Eke
Keith Warner
Dean Kalahan
James Benson
Dianne Hackborn

Walter Hahn
Thomas Savarino
Noah Friedman
Eric Willisson
Jeffrey Gilmore
John Bennett
Glenn McDavid

Brian Turner

Peter Bagaric

Martin Dahl Nielsen
Broc Stenman

Gabriel Scherer
Roice Nelson
Felipe Pait
Kenneth Hertz

Luis Bruno


Andrew Lottmann
Alex Morse

Mads Bach Villadsen
Noam Zeilberger

Buffy Lyon

Josh Wilcox

Danny Borg

Krishna Bhogaonker
Harald Tveit Alvestrand


Tarek A. Hijaz, MD
Jouni Pohjola
Chavdar Petkov
Markus Jöbstl
Bjørn Borud


Sarah G

William Straub

Frank Harper
Carsten Führmann
Rick Angel
Drew Armstrong

Jesimpson

Valeria de Paiva
Ron Prater
David Tanzer

Rafael Laguna
Miguel Esteves dos Santos
Sophie Dennison-Gibby




Randy Drexler
Peter Haggstrom


Jerzy Michał Pawlak
Santini Basra
Jenny Meyer


John Iskra

Bruce Jones
Māris Ozols
Everett Rubel



Mike D
Manik Uppal
Todd Trimble

Federer Fanatic

Forrest Samuel, Harmos Consulting








Annie Wynn
Norman and Marcia Dresner



Daniel Mattingly
James W. Crosby








Jennifer Booth
Greg Randolph





Dave and Karen Deeter

Sarah Truebe










Jeffrey Salfen
Birian Abelson

Logan McDonald

Brian Truebe
Jon Leland






Sarah Lim







James Turnbull




John Huerta
Katie Mandel Bruce
Bethany Summer






Anna Gladstone



Naom Hart
Aaron Riley

Giampiero Campa

Julie A. Sylvia


Pace Willisson









Bangskij










Peter Herschberg

Alaistair Farrugia


Conor Hennessy




Stephanie Mohr




Torinthiel


Lincoln Muri
Anet Ferwerda


Hanna





Michelle Lee Guiney

Ben Doherty
Trace Hagemann







Ryan Mannion


Penni and Terry O'Hearn



Brian Bassham
Caitlin Murphy
John Verran






Susan


Alexander Hawson
Fabrizio Mafessoni
Anita Phagan
Nicolas Acuña
Niklas Brunberg

Adam Luptak
V. Lazaro Zamora






Branford Werner
Niklas Starck Westerberg
Luca Zenti and Marta Veneziano


Ilja Preuß
Christopher Flint

George Read
Courtney Leigh

Katharina Spoerri


Daniel Risse



Hanna
Charles-Etienne Jamme
rhackman41



Jeff Leggett

RKBookman


Aaron Paul
Mike Metzler


Patrick Leiser

Melinda

Ryan Vaughn
Kent Crispin

Michael Teague

Ben



Fabian Bach
Steven Canning


Betsy McCall

John Rees

Mary Peters

Shane Claridge
Thomas Negovan
Tom Grace
Justin Jones


Jason Mitchell




Josh Weber
Rebecca Lynne Hanginger
Kirby


Dawn Conniff


Michael T. Astolfi



Kristeva

Erik
Keith Uber

Elaine Mazerolle
Matthieu Walraet

Linda Penfold




Lujia Liu



Keith



Samar Tareem


Henrik Almén
Michael Deakin


Erin Bassett
James Crook



Junior Eluhu
Dan Laufer
Carl
Robert Solovay






Silica Magazine







Leonard Saers
Alfredo Arroyo García



Larry Yu













John Behemonth


Eric Humphrey








Øystein Risan Borgersen
David Anderson Bell III











Ole-Morten Duesend







Adam North and Gabrielle Falquero

Robert Biegler


Qu Wenhao






Steffen Dittmar




Shanna Germain






Adam Blinkinsop







John WS Marvin (Dread Unicorn Games)


Bill Carter
Darth Chronis



Lawrence Stewart

Gareth Hodges

Colin Backhurst
Christopher Metzger

Rachel Gumper


Mariah Thompson

Falk Alexander Glade
Johnathan Salter




Maggie Unkefer
Shawna Maryanovich






Wilhelm Fitzpatrick
Dylan “ExoByte” Mayo
Lynda Lee




Scott Carpenter



Charles D, Payet
Vince Rostkowski


Tim Brown
Raven Daegmorgan
Zak Brueckner


Christian Page

Adi Shavit


Steven Greenberg
Chuck Lunney



Adriel Bustamente

Natasha Anicich



Bram De Bie
Edward L






Gray Detrick
Robert


Sarah Russell

Sam Leavin

Abilash Pulicken

Isabel Olondriz
James Pierce
James Morrison


April Daniels



José Tremblay Champagne


Chris Edmonds

Hans & Maria Cummings
Bart Gasiewiski


Andy Chamard



Andrew Jackson

Christopher Wright



ichimonji10


Alan Stern
Alison W


Dag Henrik Bråtane





Martin Nilsson


William Schrade___

posted image

2017-02-17 21:48:09 (31 comments; 14 reshares; 83 +1s; )Open 

The Crackpot Index for Media Content

It was bound to happen eventually: my "crackpot index" has been adapted for use in news reporting. I like it!

But in case you missed the original, here it is:

The Crackpot Index

A simple method for rating potentially revolutionary contributions to physics:

1. A -5 point starting credit.

2. 1 point for every statement that is widely agreed on to be false.

3. 2 points for every statement that is clearly vacuous.

4. 3 points for every statement that is logically inconsistent.

5. 5 points for each such statement that is adhered to despite careful correction.

6. 5 points for using a thought experiment that contradicts the results of a widely accepted real experiment.

7. 5 points for each word in all capital... more »

The Crackpot Index for Media Content

It was bound to happen eventually: my "crackpot index" has been adapted for use in news reporting. I like it!

But in case you missed the original, here it is:

The Crackpot Index

A simple method for rating potentially revolutionary contributions to physics:

1. A -5 point starting credit.

2. 1 point for every statement that is widely agreed on to be false.

3. 2 points for every statement that is clearly vacuous.

4. 3 points for every statement that is logically inconsistent.

5. 5 points for each such statement that is adhered to despite careful correction.

6. 5 points for using a thought experiment that contradicts the results of a widely accepted real experiment.

7. 5 points for each word in all capital letters (except for those with defective keyboards).

8. 5 points for each mention of "Einstien", "Hawkins" or "Feynmann".

9. 10 points for each claim that quantum mechanics is fundamentally misguided (without good evidence).

10. 10 points for pointing out that you have gone to school, as if this were evidence of sanity.

11. 10 points for beginning the description of your theory by saying how long you have been working on it. (10 more for emphasizing that you worked on your own.)

12. 10 points for mailing your theory to someone you don't know personally and asking them not to tell anyone else about it, for fear that your ideas will be stolen.

13. 10 points for offering prize money to anyone who proves and/or finds any flaws in your theory.

14. 10 points for each new term you invent and use without properly defining it.

15. 10 points for each statement along the lines of "I'm not good at math, but my theory is conceptually right, so all I need is for someone to express it in terms of equations".

16. 10 points for arguing that a current well-established theory is "only a theory", as if this were somehow a point against it.

17. 10 points for arguing that while a current well-established theory predicts phenomena correctly, it doesn't explain "why" they occur, or fails to provide a "mechanism".

18. 10 points for each favorable comparison of yourself to Einstein, or claim that special or general relativity are fundamentally misguided (without good evidence).

19. 10 points for claiming that your work is on the cutting edge of a "paradigm shift".

20. 20 points for emailing me and complaining about the crackpot index. (E.g., saying that it "suppresses original thinkers" or saying that I misspelled "Einstein" in item 8.)

21. 20 points for suggesting that you deserve a Nobel prize.

22. 20 points for each favorable comparison of yourself to Newton or claim that classical mechanics is fundamentally misguided (without good evidence).

23. 20 points for every use of science fiction works or myths as if they were fact.

24. 20 points for defending yourself by bringing up (real or imagined) ridicule accorded to your past theories.

25. 20 points for naming something after yourself. (E.g., talking about the "The Evans Field Equation" when your name happens to be Evans.)

26. 20 points for talking about how great your theory is, but never actually explaining it.

27. 20 points for each use of the phrase "hidebound reactionary".

28. 20 points for each use of the phrase "self-appointed defender of the orthodoxy".

29. 30 points for suggesting that a famous figure secretly disbelieved in a theory which he or she publicly supported. (E.g., that Feynman was a closet opponent of special relativity, as deduced by reading between the lines in his freshman physics textbooks.)

30. 30 points for suggesting that Einstein, in his later years, was groping his way towards the ideas you now advocate.

31. 30 points for claiming that your theories were developed by an extraterrestrial civilization (without good evidence).

32. 30 points for allusions to a delay in your work while you spent time in an asylum, or references to the psychiatrist who tried to talk you out of your theory.

33. 40 points for comparing those who argue against your ideas to Nazis, stormtroopers, or brownshirts.

34. 40 points for claiming that the "scientific establishment" is engaged in a "conspiracy" to prevent your work from gaining its well-deserved fame, or suchlike.

35. 40 points for comparing yourself to Galileo, suggesting that a modern-day Inquisition is hard at work on your case, and so on.

36. 40 points for claiming that when your theory is finally appreciated, present-day science will be seen for the sham it truly is. (30 more points for fantasizing about show trials in which scientists who mocked your theories will be forced to recant.)

37. 50 points for claiming you have a revolutionary theory but giving no concrete testable predictions.

http://math.ucr.edu/home/baez/crackpot.html___

posted image

2017-02-17 19:53:01 (16 comments; 9 reshares; 88 +1s; )Open 

Weird machines

At a workshop on cybersecurity at the Santa Fe Institute, I heard about the concept of weird machines. The description was poetic:

They hide in dark spaces — semantic gaps between levels of abstraction.

In short, they're not monsters like the Terminator here, but computer programs that do things you didn't think possible... because your way of thinking about a computer had gaps:

In computer security, the weird machine is a computational artifact where additional code execution can happen outside the original specification of the program. It is closely related to the concept of weird instructions, which are the building blocks of an exploit based on crafted input data. The functionality of the weird machine is invoked through unexpected inputs.

While expected, valid input activates the normal,i... more »

Weird machines

At a workshop on cybersecurity at the Santa Fe Institute, I heard about the concept of weird machines. The description was poetic:

They hide in dark spaces — semantic gaps between levels of abstraction.

In short, they're not monsters like the Terminator here, but computer programs that do things you didn't think possible... because your way of thinking about a computer had gaps:

In computer security, the weird machine is a computational artifact where additional code execution can happen outside the original specification of the program. It is closely related to the concept of weird instructions, which are the building blocks of an exploit based on crafted input data. The functionality of the weird machine is invoked through unexpected inputs.

While expected, valid input activates the normal, intended functionality in a computer program, input that was unexpected by the program developer may activate unintended functionality. The weird machine consists of this unintended functionality that can be programmed with selected inputs in an exploit.

In a classical attack taking advantage of a stack buffer overflow, the input given to a vulnerable program is crafted and delivered so that it itself becomes executed as program code. However, if the data areas of the program memory have been protected so that they cannot be executed directly like this, the input may instead take the form of pointers into pieces of existing program code that then become executed in an unexpected order to generate the functionality of the exploit. These snippets of code that are used by the exploit are referred to as gadgets in the context of return-oriented programming.

Through interpretation of data as code, weird machine functionality that is by definition outside the original program specification can be reached also by Proof-Carrying Code, which has been formally proven to function in a certain specific way. This disparity is essentially caused by a disconnect between formal abstract modelling of a computer program and its real-world instance, which can be influenced by events that are not captured in the original abstraction, such as memory errors or power outages.

If you think about it, such things as viruses, prions and cancer also exploit gaps between a simplified abstract model of how organisms work, and the real world of chemistry with all its myriad possibilities.

For more, try this:

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

Buttons

A special service of CircleCount.com is the following button.

The button shows the number of followers you have directly on a small button. You can add this button to your website, like the +1-Button of Google or the Like-Button of Facebook.



You can add this button directly in your website. For more information about the CircleCount Buttons and the description how to add them to another page click here.

John BaezCircloscope