Adonis Diaries

Archive for the ‘sciences’ Category

Here’s Why Some Brains Really Are Smarter, According to This New Study

Note: Mind you that smart is Not solely restricted to analytical reasoning. There are many kinds of smartness and intelligence in human behaviors.

Are you ‘neurally efficient‘?

MIKE MCRAE
18 MAY 2018

People with a higher IQ are more likely to have fewer connections between the neurons in the outer layer of their brain, according to a recent study.

While previous research has suggested bigger brains are indeed smarter, a closer look at the microstructural architecture suggests it’s not just a matter of more brain cells, as much as more efficiently connected ones.

An international team of neurologists used a non-invasive technique known as multi-shell diffusion tensor imaging to get an idea of the density and branching arrangements of the grey matter inside the heads of just under 260 volunteers.

Each subject also took a culturally fair complex reasoning test, producing a variety of scores ranging from 7 to 27 correct answers out of a possible 28.

Matching the imaging data with the test scores, the researchers found that those with higher analytical skills not only had more brain cells, they also tended to have fewer branches between the neurons in their cerebral cortex.

They then turned to a database of nearly 500 neural maps within the Human Connectome Project, and found the same pattern of higher IQ and lower inter-connectivity.

At first this might seem counter-intuitive. (If we are restricting smartness with analytical reasoning)

The old idiom ‘more hands make light work’ might apply to brain cells, but in this case those extra hands don’t seem to be passing more information between them.

Previous research had shown that in spite of having more brain cells to share the heavy lifting, smarter brains don’t tend to work as hard, displaying less metabolic activity when subjected to an IQ test compared with those who struggle to attain high scores.

This observation has led to the development of the neural efficiency hypothesis, which suggests the analytical power of groups of nerve cells isn’t about pushing them harder, but about them being connected in a way that minimises effort.

“Intelligent brains are characterised by a slim but efficient network of their neurons,” says neurologist Erhan Genç from Ruhr-University Bochum in Germany.

This makes it possible to achieve a high level of thinking with the least possible neural activity.

Research on intelligence is often complicated by questions of definition and interpretations of IQ testing, so we need to refrain from generalising the results too far beyond the scope of the experiment.

Brains do a number of awesome things, with analytical reasoning making up just a part of its diverse cognitive skill set.

But understanding more about how individual units can interact to solve problems with maximum efficiency does more than show how brains function on a cellular level, they might point the way to improving technology that mimics them.

More research will no doubt help unravel the mystery of just how a streamlined nervous system does a better job at solving problems.

It might not help us all become geniuses, but it does show there’s merit in working smarter, and not harder.

This researcher was published in Nature Communications

Are you ‘neurally efficient’?

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Water on Mars?

Mars has liquid water just below its surface, according to new measurements by Nasa’s Curiosity rover.

Until now, scientists had thought that conditions on the red planet were too cold and arid for liquid water to exist, although there were known to be deposits of ice.

Prof Andrew Coates, head of planetary science at the Mullard Space Mullard Space Science Laboratory, University College London, said: “The evidence so far is that any water would be in the form of permafrost. It’s the first time we’ve had evidence of liquid water there now.”

The latest findings suggest that Martian soil is damp with liquid brine, due to the presence of a salt that significantly lowers the freezing point of water.

When mixed with calcium perchlorate liquid, water can exist down to around -70C, and the salt also soaks up water vapour from the atmosphere.

New measurements from the Gale crater show that during winter nights until just after sunrise, temperatures and humidity levels are just right for liquid brine to form.

Morten Bo Madsen, a senior Mars scientist at the University of Copenhagen and a co-investigator on the Curiosity rover, said: “The soil is porous, so what we are seeing is that the water seeps down through the soil. Over time, other salts may also dissolve in the soil and now that they are liquid, they can move and precipitate elsewhere under the surface.”

Liquid water is traditionally considered an essential ingredient for life as we known it, but Mars remains hostile for other reasons, the scientists said. The latest findings are unlikely to change the view that if life ever blossomed on Mars, it probably died out more than a billion years ago.

“There are organisms on Earth, halophiles, that can survive in salty environments, but if it’s also very cold and very dry that’s a problem” said Madsen. “The radiation on Mars nails it – that environment is very hostile.”

Prof Coates agreed: “Liquid water is one of the conditions you need for life, it’s not all of them.”

On Earth, the global magnetic field protects the atmosphere from being degraded by harmful cosmic radiation from the Sun. In the past, scientists believe that Mars had a similar magnetic field and thicker atmosphere, but that the field was lost around four billion years ago.

Today, cosmic radiation penetrates at least one metre into the Martian surface and would kill even the most robust microbes known on Earth.

Surface temperatures on Mars range from around 20C at noon, at the equator, down to lows of around −153C at the poles.

The presence of perchlorate salts was discovered in 2008, but until now if was not known whether temperatures and humidity would be high enough to produce liquid brine.

The latest paper, published in Nature, analyses humidity and temperature data for a full Martian year, showing that liquid brine ought to form. Instruments on-board Curiosity also measured estimates of subsurface water concentration, which suggested that water was indeed being absorbed from the air and the surface frost by the salty soil.

The water would be present in tiny quantities between the grains of soil, rather than in droplet form. “If you dug a trench you might see that the soil at the base was a bit darker,” said Madsen.

Curiosity landed on Mars in 2012 in the large crater, Gale, located just south of the equator. The giant crater is 154 kilometres in diameter and the rim of the crater is almost five kilometres high.

In the middle of the crater lies Mount Sharp, which Curiosity is currently ascending.

Observations by the Mars probe’s stereo camera have previously shown areas characteristic of old riverbed, with rounded pebbles that indicate there were flowing rivers up to one metre deep in the past.

The latest close-up images show slanting expanses of sedimentary deposits, lying one above the other. “These kind of deposits are formed when large amounts of water flow down the slopes of the crater and these streams of water meet the stagnant water in the form of a lake,” said Madsen.

Patsy Z shared this link. 14 hrs ·

And then there was water! smile emoticon

New measurements from the Gale crater contradict theories that the planet is too cold for liquid water to exist, but Mars still considered hostile to life
theguardian.com|By Hannah Devlin

The Failed Experiment That Changed The World

In science, we don’t simply perform experiments willy-nilly. We don’t put things together at random and ask, “what happens if I do this?” We examine the phenomena that exist, the predictions our theories make, and look for ways to test them in ever-greater detail.

Sometimes, they give extraordinary agreement to new precision, confirming what we had thought. Sometimes, they disagree, pointing the way to new physics. And sometimes, they fail to give any non-zero result at all.

In the 1880s, an incredibly precise experiment failed in exactly this fashion, and paved the way for relativity and quantum mechanics in doing so.

Ethan Siegel, Contributor

The orbits of the planets and comets, among other celestial objects, are governed by the laws of universal gravitation.

Kay Gibson, Ball Aerospace & Technologies Corp

The orbits of the planets and comets, among other celestial objects, are governed by the laws of universal gravitation.

Let’s go even farther back in history to understand why this was such a big deal. Gravitation was the first of the forces to be understood, as Newton had put forth his law of universal gravitation in the 1600s, explaining both the motions of bodies on Earth and in space.

A few decades later (in 1704) Newton also put forth a theory of light — the corpuscular theory — that stated that light was made up of particles, that these particles are rigid and weightless, and that they move in a straight line unless something causes them to reflect, refract or diffract.

Light's properties, such as reflection and refraction, appear to be corpuscular-like, but there are wave-like phenomena it exhibits as well.

Wikimedia Commons user Spigget

Light’s properties, such as reflection and refraction, appear to be corpuscular-like, but there are wave-like phenomena it exhibits as well.

This accounted for a lot of observed phenomena, including the realization that white light was the combination of all other colors of light. But as time went on, many experiments revealed the wave nature of light, an alternative explanation from Christiaan Huygens, one of Newton’s contemporaries.

Light's properties, such as reflection and refraction, appear to be corpuscular-like, but there are wave-like phenomena it exhibits as well.

Wikimedia Commons user Lookang

When any wave — water waves, sound waves, or light waves — are passed through a double slit, the waves create an interference pattern.

Huygens proposed instead that every point which can be considered a source of light, including from a light wave simply traveling forward, acted like a wave, with a spherical wavefront emanating from each of those points.

Although many experiments would give the same results whether you took Newton’s approach or Huygens’ approach, there were a few that took place beginning in 1799 that really began to show how powerful the wave theory was.

Light of different wavelengths, when passed through a double slit, exhibit the same wave-like properties that other waves do.

MIT Physics department Technical Services Group

Light of different wavelengths, when passed through a double slit, exhibit the same wave-like properties that other waves do.

By isolating different colors of light and passing them through either single slits, double slits or diffraction gratings, scientists were able to observe patterns that could only be produced if light was a wave. Indeed, the patterns produced — with peaks and troughs — mirrored that of well-known waves, like water waves.

The wave-like properties of light became even better understood thanks to Thomas Young's two-slit experiments, where constructive and destructive interference showed themselves dramatically.

Thomas Young, 1801

The wave-like properties of light became even better understood thanks to Thomas Young’s two-slit experiments, where constructive and destructive interference showed themselves dramatically.

But water waves — as it was well-known — traveled through the medium of water. Take away the water, and there’d be no wave! This was true of all known wave phenomena: sound, which is a compression and rarefaction, needs a medium to travel through as well.

If you take away all matter, there’s no medium for sound to travel through, and hence why they say, “In space, no one can hear you scream.”

In space, sounds that are produced on Earth will never travel to you, since there's no medium for sound to travel through between the Earth and you.

NASA/Marshall Space Flight Centre

In space, sounds that are produced on Earth will never travel to you, since there’s no medium for sound to travel through between the Earth and you.

So, then, the reasoning went, if light is a wave — albeit, as Maxwell demonstrated in the 1860s, an electromagnetic wave — it, too, must have a medium that it travels through. Although no one could measure this medium, it was given a name: the luminiferous aether.

Sounds like a silly idea now, doesn’t it? But it wasn’t a bad idea at all. In fact, it had all the hallmarks of a great scientific idea, because it not only built upon the science that had been established previously, but this idea made new predictions that were testable! Let me explain by using an analogy: the water in a rapidly moving river.

The Klamath River, flowing through a valley, is an example of a rapidly moving body of water.

Blake, Tupper Ansel, U.S. Fish and Wildlife Service

The Klamath River, flowing through a valley, is an example of a rapidly moving body of water.

Imagine that you throw a rock into a raging river, and watch the waves that it makes. If you follow the ripples of the wave towards the banks, perpendicular to the direction of the current, the wave will move at a particular speed.

But what if you watch the wave move upstream? It’s going to move more slowly, because the medium that the wave is traveling through, the water, is moving! And if you watch the wave move downstream, it’ll move more quickly, again because the medium is moving.

Even though the luminiferous aether had never been detected or measured, there was an ingenious experiment devised by Albert A. Michelson that applied this same principle to light.

The Earth, moving in its orbit around the Sun and spinning on its axis, should provide an extra motion if there's any medium that light travels through.

Larry McNish, RASC Calgary

The Earth, moving in its orbit around the Sun and spinning on its axis, should provide an extra motion if there’s any medium that light travels through.

You see, even though we didn’t know exactly how the aether was oriented in space, what its direction was or how it was flowing, or what was at rest with respect to it, presumably — like Newtonian space — it was absolute. It existed independently of matter, as it must considering that light could travel where sound could not: in a vacuum.

So, in principle, if you measured the speed at which light moved when the Earth was moving “upstream” or “downstream” (or perpendicular to the aether’s “stream”, for that matter), you could not only detect the existence of the aether, you could determine what the rest frame of the Universe was!

the speed of light is something like 186,282 miles-per-second (Michelson knew it to be 186,350 ± 30 miles-per-second), while the Earth’s orbital speed is only about 18.5 miles-per-second, something we weren’t good enough to measure in the 1880s.

But Michelson had a trick up his sleeve.

The original design of a Michelson interferometer.

Albert Abraham Michelson, 1881

The original design of a Michelson interferometer.

In 1881, Michelson developed and designed what’s now known as a Michelson interferometer, which was absolutely brilliant. What it did was built on the fact that light — being made of waves — interferes with itself. And in particular, if he took a light wave, split it into two components that were perpendicular to one another (and hence, moving differently with respect to the aether), and had the two beams travel exactly identical distances and then reflect them back towards one another, he would observe a shift in the interference pattern generated by them!

You see, if the entire apparatus was stationary with respect to the aether, there would be no shift in the interference pattern they made, but if it moves at all in one direction more than the other, you would get a shift.

If you split light into two perpendicular components and bring them back together, they'll interfere. If you move in one direction versus another, that interference pattern will shift.

Wikimedia commons user Stigmatella aurantiaca

If you split light into two perpendicular components and bring them back together, they’ll interfere. If you move in one direction versus another, that interference pattern will shift.

Michelson’s original design was unable to detect any shift, but with an arm length of just 1.2 meters, his expected shift of 0.04 fringes was just above the limit of what he could detect, which was about 0.02 fringes.

There were also alternatives to the idea that the aether was purely stationary — such as the idea that it was dragged by the Earth (although it couldn’t be completely, because of observations of how stellar aberration worked) — so he performed the experiment at multiple times throughout the day, as the rotating Earth would have to be oriented at different angles with respect to the aether.

The null result was interesting, but not completely convincing. Over the subsequent six years, he designed an interferometer 10 times as large (and hence, ten times as precise) with Edward Morley, and the two of them in 1887 performed what’s now known as the Michelson-Morley experiment.

They expected a fringe-shift throughout the day of up to 0.4 fringes, with an accuracy down to 0.01 fringes.

Thanks to the internet, here are the original 1887 results!

The lack of an observed shift, despite the necessary sensitivity and the theoretical predictions, was an incredible achievement that led to the development of modern physics.

Michelson, A. A.; Morley, E. (1887). “On the Relative Motion of the Earth and the Luminiferous Ether”. American Journal of Science 34 (203): 333–345

The lack of an observed shift, despite the necessary sensitivity and the theoretical predictions, was an incredible achievement that led to the development of modern physics.

This null result — the fact that there was no luminiferous aether — was actually a huge advance for modern science, as it meant that light must have been inherently different from all other waves that we knew of.

The resolution came 18 years later, when Einstein’s theory of special relativity came along. And with it, we gained the recognition that the speed of light was a universal constant in all reference frames, that there was no absolute space or absolute time, and — finally — that light needed nothing more than space and time to travel through.

Albert Michelson won the Nobel Prize in 1907 for his work developing the interferometer and the advances made because of his measurements. It was the most important null result in scientific history.

Nobel foundation, via nobelprize.org

Albert Michelson won the Nobel Prize in 1907 for his work developing the interferometer and the advances made because of his measurements. It was the most important null result in scientific history.

The experiment — and Michelson’s body of work — was so revolutionary that he became the only person in history to have won a Nobel Prize for a very precise non-discovery of anything. The experiment itself may have been a complete failure, but what we learned from it was a greater boon to humanity and our understanding of the Universe than any success would have been!

Astrophysicist and author Ethan Siegel is the founder and primary writer of Starts With A Bang! Check out his first book, Beyond The Galaxy, and look for his second, Treknology, this October!

Are you obsessed with symmetry?

On the 30th of May, 1832, a gunshot was heard ringing out across the 13th arrondissement in Paris.

A peasant, who was walking to market that morning, ran towards where the gunshot had come from, and found a young man writhing in agony on the floor, clearly shot by a dueling wound. The young man’s name was Evariste Galois, a mathematician who started modern math. He was a well-known revolutionary in Paris at the time. Galois was taken to the local hospital where he died the next day in the arms of his brother. And the last words he said to his brother were, “Don’t cry for me, Alfred. I need all the courage I can muster to die at the age of 20.”

0:55 It wasn’t, in fact, revolutionary politics for which Galois was famous. But a few years earlier, while still at school, he’d actually cracked one of the big mathematical problems at the time. And he wrote to the academicians in Paris, trying to explain his theory. But the academicians couldn’t understand anything that he wrote. (Laughter) This is how he wrote most of his mathematics.

the night before that duel, he realized this possibly is his last chance to try and explain his great breakthrough. So he stayed up the whole night, writing away, trying to explain his ideas.

And as the dawn came up and he went to meet his destiny, he left this pile of papers on the table for the next generation. Maybe the fact that he stayed up all night doing mathematics was the fact that he was such a bad shot that morning and got killed.

But contained inside those documents was a new language, a language to understand one of the most fundamental concepts of science — namely symmetry. Now, symmetry is almost nature’s language. It helps us to understand so many different bits of the scientific world. For example, molecular structure. What crystals are possible, we can understand through the mathematics of symmetry.

In microbiology you really don’t want to get a symmetrical object, because they are generally rather nasty. The swine flu virus, at the moment, is a symmetrical object. And it uses the efficiency of symmetry to be able to propagate itself so well. But on a larger scale of biology, actually symmetry is very important, because it actually communicates genetic information.

I’ve taken two pictures here and I’ve made them artificially symmetrical. And if I ask you which of these you find more beautiful, you’re probably drawn to the lower two. Because it is hard to make symmetry. And if you can make yourself symmetrical, you’re sending out a sign that you’ve got good genes, you’ve got a good upbringing and therefore you’ll make a good mate. So symmetry is a language which can help to communicate genetic information.

Symmetry can also help us to explain what’s happening in the Large Hadron Collider in CERN. Or what’s not happening in the Large Hadron Collider in CERN.

To be able to make predictions about the fundamental particles we might see there, it seems that they are all facets of some strange symmetrical shape in a higher dimensional space.

I think Galileo summed up, very nicely, the power of mathematics to understand the scientific world around us. He wrote, “The universe cannot be read until we have learnt the language and become familiar with the characters in which it is written. It is written in mathematical language, and the letters are triangles, circles and other geometric figures, without which means it is humanly impossible to comprehend a single word.”

it’s not just scientists who are interested in symmetry. Artists too love to play around with symmetry. They also have a slightly more ambiguous relationship with it. Here is Thomas Mann talking about symmetry in “The Magic Mountain.” He has a character describing the snowflake, and he says he “shuddered at its perfect precision, found it deathly, the very marrow of death.” 

what artists like to do is to set up expectations of symmetry and then break them. And a beautiful example of this I found, actually, when I visited a colleague of mine in Japan, Professor Kurokawa. And he took me up to the temples in Nikko. And just after this photo was taken we walked up the stairs. And the gateway you see behind has eight columns, with beautiful symmetrical designs on them. Seven of them are exactly the same, and the eighth one is turned upside down.

And I said to Professor Kurokawa, “Wow, the architects must have really been kicking themselves when they realized that they’d made a mistake and put this one upside down.” And he said, “No, no, no. It was a very deliberate act.” And he referred me to this lovely quote from the Japanese Essays in Idleness” from the 14th century, in which the essayist wrote, “In everything, uniformity is undesirable. Leaving something incomplete makes it interesting, and gives one the feeling that there is room for growth.” Even when building the Imperial Palace, they always leave one place unfinished.

if I had to choose one building in the world to be cast out on a desert island, to live the rest of my life, being an addict of symmetry, I would probably choose the Alhambra in Granada.

This is a palace celebrating symmetry. Recently I took my family — we do these rather kind of nerdy mathematical trips, which my family love. This is my son Tamer. You can see he’s really enjoying our mathematical trip to the Alhambra. But I wanted to try and enrich him. I think one of the problems about school mathematics is it doesn’t look at how mathematics is embedded in the world we live in. So, I wanted to open his eyes up to how much symmetry is running through the Alhambra.

You see it already. Immediately you go in, the reflective symmetry in the water. But it’s on the walls where all the exciting things are happening. The Moorish artists were denied the possibility to draw things with souls. So they explored a more geometric art. And so what is symmetry? The Alhambra somehow asks all of these questions. What is symmetry? When [there] are two of these walls, do they have the same symmetries? Can we say whether they discovered all of the symmetries in the Alhambra?

 it was Galois who produced a language to be able to answer some of these questions. For Galois, symmetry — unlike for Thomas Mann, which was something still and deathly — for Galois, symmetry was all about motion. What can you do to a symmetrical object, move it in some way, so it looks the same as before you moved it? I like to describe it as the magic trick moves. What can you do to something? You close your eyes. I do something, put it back down again. It looks like it did before it started.

for example, the walls in the Alhambra — I can take all of these tiles, and fix them at the yellow place, rotate them by 90 degrees, put them all back down again and they fit perfectly down there. And if you open your eyes again, you wouldn’t know that they’d moved. But it’s the motion that really characterizes the symmetry inside the Alhambra. But it’s also about producing a language to describe this. And the power of mathematics is often to change one thing into another, to change geometry into language.

I’m going to take you through, perhaps push you a little bit mathematically — so brace yourselves — push you a little bit to understand how this language works, which enables us to capture what is symmetry.

let’s take these two symmetrical objects here. Let’s take the twisted six-pointed starfish. What can I do to the starfish which makes it look the same? Well, there I rotated it by a sixth of a turn, and still it looks like it did before I started. I could rotate it by a third of a turn, or a half a turn, or put it back down on its image, or two thirds of a turn. And a fifth symmetry, I can rotate it by five sixths of a turn. And those are things that I can do to the symmetrical object that make it look like it did before I started.

for Galois, there was actually a sixth symmetry. Can anybody think what else I could do to this which would leave it like I did before I started? I can’t flip it because I’ve put a little twist on it, haven’t I? It’s got no reflective symmetry. But what I could do is just leave it where it is, pick it up, and put it down again. And for Galois this was like the zeroth symmetry. Actually, the invention of the number zero was a very modern concept, seventh century A.D., by the Indians. It seems mad to talk about nothing. And this is the same idea. This is a symmetrical — so everything has symmetry, where you just leave it where it is.

 this object has six symmetries. And what about the triangle? Well, I can rotate by a third of a turn clockwise or a third of a turn anticlockwise. But now this has some reflectional symmetry. I can reflect it in the line through X, or the line through Y, or the line through Z. Five symmetries and then of course the zeroth symmetry where I just pick it up and leave it where it is. So both of these objects have six symmetries. Now, I’m a great believer that mathematics is not a spectator sport, and you have to do some mathematics in order to really understand it.

 here is a little question for you. And I’m going to give a prize at the end of my talk for the person who gets closest to the answer. The Rubik’s Cube. How many symmetries does a Rubik’s Cube have? How many things can I do to this object and put it down so it still looks like a cube? Okay? So I want you to think about that problem as we go on, and count how many symmetries there are. And there will be a prize for the person who gets closest at the end.

 let’s go back down to symmetries that I got for these two objects. What Galois realized: it isn’t just the individual symmetries, but how they interact with each other which really characterizes the symmetry of an object. If I do one magic trick move followed by another, the combination is a third magic trick move. And here we see Galois starting to develop a language to see the substance of the things unseen, the sort of abstract idea of the symmetry underlying this physical object. For example, what if I turn the starfish by a sixth of a turn, and then a third of a turn?

I’ve given names. The capital letters, A, B, C, D, E, F, are the names for the rotations. B, for example, rotates the little yellow dot to the B on the starfish. And so on. So what if I do B, which is a sixth of a turn, followed by C, which is a third of a turn? Well let’s do that. A sixth of a turn, followed by a third of a turn, the combined effect is as if I had just rotated it by half a turn in one go. So the little table here records how the algebra of these symmetries work. I do one followed by another, the answer is it’s rotation D, half a turn. What I if I did it in the other order? Would it make any difference? Let’s see. Let’s do the third of the turn first, and then the sixth of a turn. Of course, it doesn’t make any difference. It still ends up at half a turn.

And there is some symmetry here in the way the symmetries interact with each other. But this is completely different to the symmetries of the triangle. Let’s see what happens if we do two symmetries with the triangle, one after the other. Let’s do a rotation by a third of a turn anticlockwise, and reflect in the line through X. Well, the combined effect is as if I had just done the reflection in the line through Z to start with. Now, let’s do it in a different order. Let’s do the reflection in X first, followed by the rotation by a third of a turn anticlockwise. The combined effect, the triangle ends up somewhere completely different. It’s as if it was reflected in the line through Y.

it matters what order you do the operations in.

And this enables us to distinguish why the symmetries of these objects — they both have six symmetries. So why shouldn’t we say they have the same symmetries? But the way the symmetries interact enable us — we’ve now got a language to distinguish why these symmetries are fundamentally different. And you can try this when you go down to the pub, later on. Take a beer mat and rotate it by a quarter of a turn, then flip it. And then do it in the other order, and the picture will be facing in the opposite direction.

Galois produced some laws for how these tables — how symmetries interact. It’s almost like little Sudoku tables.

You don’t see any symmetry twice in any row or column. And, using those rules, he was able to say that there are in fact only two objects with six symmetries. And they’ll be the same as the symmetries of the triangle, or the symmetries of the six-pointed starfish. I think this is an amazing development. It’s almost like the concept of number being developed for symmetry. In the front here, I’ve got one, two, three people sitting on one, two, three chairs. The people and the chairs are very different, but the number, the abstract idea of the number, is the same.

we can see this now: we go back to the walls in the Alhambra. Here are two very different walls, very different geometric pictures. But, using the language of Galois, we can understand that the underlying abstract symmetries of these things are actually the same.

For example, let’s take this beautiful wall with the triangles with a little twist on them. You can rotate them by a sixth of a turn if you ignore the colors. We’re not matching up the colors. But the shapes match up if I rotate by a sixth of a turn around the point where all the triangles meet. What about the center of a triangle? I can rotate by a third of a turn around the center of the triangle, and everything matches up. And then there is an interesting place halfway along an edge, where I can rotate by 180 degrees. And all the tiles match up again. So rotate along halfway along the edge, and they all match up.

 let’s move to the very different-looking wall in the Alhambra. And we find the same symmetries here, and the same interaction. So, there was a sixth of a turn. A third of a turn where the Z pieces meet. And the half a turn is halfway between the six pointed stars. And although these walls look very different, Galois has produced a language to say that in fact the symmetries underlying these are exactly the same. And it’s a symmetry we call 6-3-2.

Here is another example in the Alhambra. This is a wall, a ceiling, and a floor. They all look very different. But this language allows us to say that they are representations of the same symmetrical abstract object, which we call 4-4-2. Nothing to do with football, but because of the fact that there are two places where you can rotate by a quarter of a turn, and one by half a turn.

this power of the language is even more, because Galois can say, “Did the Moorish artists discover all of the possible symmetries on the walls in the Alhambra?” And it turns out they almost did.

You can prove, using Galois’ language, there are actually only 17 different symmetries that you can do in the walls in the Alhambra. And they, if you try to produce a different wall with this 18th one, it will have to have the same symmetries as one of these 17.

these are things that we can see. And the power of Galois’ mathematical language is it also allows us to create symmetrical objects in the unseen world, beyond the two-dimensional, three-dimensional, all the way through to the four- or five- or infinite-dimensional space. And that’s where I work. I create mathematical objects, symmetrical objects, using Galois’ language, in very high dimensional spaces. So I think it’s a great example of things unseen, which the power of mathematical language allows you to create.

like Galois, I stayed up all last night creating a new mathematical symmetrical object for you, and I’ve got a picture of it here. Well, unfortunately it isn’t really a picture. If I could have my board at the side here, great, excellent. Here we are. Unfortunately, I can’t show you a picture of this symmetrical object. But here is the language which describes how the symmetries interact.

this new symmetrical object does not have a name yet. Now, people like getting their names on things, on craters on the moon or new species of animals. So I’m going to give you the chance to get your name on a new symmetrical object which hasn’t been named before. And this thing — species die away, and moons kind of get hit by meteors and explode — but this mathematical object will live forever. It will make you immortal. In order to win this symmetrical object, what you have to do is to answer the question I asked you at the beginning. How many symmetries does a Rubik’s Cube have?

 Okay, I’m going to sort you out. Rather than you all shouting out, I want you to count how many digits there are in that number. Okay? If you’ve got it as a factorial, you’ve got to expand the factorials. Okay, now if you want to play, I want you to stand up, okay? If you think you’ve got an estimate for how many digits, right — we’ve already got one competitor here. If you all stay down he wins it automatically. Okay. Excellent. So we’ve got four here, five, six. Great. Excellent. That should get us going. All right.

Anybody with five or less digits, you’ve got to sit down, because you’ve underestimated. Five or less digits. So, if you’re in the tens of thousands you’ve got to sit down. 60 digits or more, you’ve got to sit down. You’ve overestimated. 20 digits or less, sit down. How many digits are there in your number? Two? So you should have sat down earlier. (Laughter) Let’s have the other ones, who sat down during the 20, up again. Okay? If I told you 20 or less, stand up. Because this one. I think there were a few here. The people who just last sat down.

 how many digits do you have in your number? (Laughs) 21. Okay good.

How many do you have in yours? 18. So it goes to this lady here. 21 is the closest. It actually has — the number of symmetries in the Rubik’s cube has 25 digits. So now I need to name this object. So, what is your name? I need your surname. Symmetrical objects generally — spell it for me. G-H-E-Z No, SO2 has already been used, actually, in the mathematical language. So you can’t have that one. So Ghez, there we go. That’s your new symmetrical object. You are now immortal. (Applause)

17:26 And if you’d like your own symmetrical object, I have a project raising money for a charity in Guatemala, where I will stay up all night and devise an object for you, for a donation to this charity to help kids get into education in Guatemala. And I think what drives me, as a mathematician, are those things which are not seen, the things that we haven’t discovered.

It’s all the unanswered questions which make mathematics a living subject. And I will always come back to this quote from the Japanese “Essays in Idleness”: “In everything, uniformity is undesirable. Leaving something incomplete makes it interesting, and gives one the feeling that there is room for growth.”

Patsy Z shared this link

“One of the problems about school mathematics is it doesn’t look at how mathematics is embedded in the world we live in.”

The beauty of math is everywhere:

The world turns on symmetry — from the spin of subatomic particles to the dizzying beauty of an arabesque.
But there’s more to it than meets the eye.
t.ted.com|By Marcus du Sautoy
From “Royal Altess” by Thomas Mann
“You think? Your are wrong. I’am not an aristocrat, I’m all the opposite, by reason and by taste.

Proof is for mathematical theorems and alcoholic beverages. It’s not for science.”

You’ll agree with me that if I decline the vivas of the people, it’s not out of pride: I have the taste of humanity and kindness.

The greatness of mankind is a miserable thing and often, it seems to me that men should know it , and conduct themselves humanly and with kindness and not to seek to be humiliated or to cow tow to one another.

Littérature et Poésie‘s photo.
In order to suffer being the object of simagrees that surround this greatness, we have to thicken our skin. I’m a little fragile by nature.
I don’t feel able to confront the ridicule of my situation. The person posted on my door and who expect to see me pass without extending him any attention or respect commensurate to the chamberlain at the door, embarrasses me. It is my way of loving the people…”
From another Mann, and from post over at Peter Guest’s blog, the scientist Michael “Hockey Stick” Mann is quoted saying:

Proof is for mathematical theorems and alcoholic beverages. It’s not for science.”

Michael Mann goes on to explain that science is all about “credible theories” and “best explanations” and his critics are not offering up any of those.

Mann’s attempt to separate proof from science stems from increasing public awareness that the warming predicted by the high-sensitivity models that Mann and others have championed just have not occurred over the last 15 years.

Quest for immortality? Here we go again

“The genitals don’t determine your gender or even really your sexual identity”.

This time with Martine Rothblatt, founder of Sirius XM satellite radio, and now heading up a drug company that makes life-saving medicines for rare diseases 

Chris Anderson: I guess what we’re going to do is we’re going to talk about your life, and using some pictures that you shared with me. And I think we should start right here with this one. Okay, now who is this?

0:25 Martine Rothblatt: This is me with our oldest son Eli. He was about age five. This is taken in Nigeria right after having taken the Washington, D.C. bar exam.

CA: But this doesn’t really look like a Martine.

MR: Right. That was myself as a male, the way I was brought up. Before I transitioned from male to female and Martin to Martine.

CA: You were brought up Martin Rothblatt.

MR: Correct.

CA: And about a year after this picture, you married a beautiful woman. Was this love at first sight? What happened there?

MR: It was love at the first sight. I saw Bina at a discotheque in Los Angeles, and we later began living together, but the moment I saw her, I saw just an aura of energy around her. I asked her to dance. She said she saw an aura of energy around me. I was a single male parent. She was a single female parent. We showed each other our kids’ pictures, and we’ve been happily married for a third of a century now. (Applause)

CA: And at the time, you were kind of this hotshot entrepreneur, working with satellites. I think you had two successful companies, and then you started addressing this problem of how could you use satellites to revolutionize radio. Tell us about that.

MR: I always loved space technology, and satellites, to me, are sort of like the canoes that our ancestors first pushed out into the water.

it was exciting for me to be part of the navigation of the oceans of the sky, and as I developed different types of satellite communication systems, the main thing I did was to launch bigger and more powerful satellites, the consequence of which was that the receiving antennas could be smaller and smaller, and after going through direct television broadcasting, I had the idea that if we could make a more powerful satellite, the receiving dish could be so small that it would just be a section of a parabolic dish, a flat little plate embedded into the roof of an automobile, and it would be possible to have nationwide satellite radio, and that’s Sirius XM today.

CA: who here has used Sirius?

2:47 (Applause)

2:50 MR: Thank you for your monthly subscriptions.

2:52 (Laughter)

CA: that succeeded despite all predictions at the time. It was a huge commercial success, but soon after this, in the early 1990s, there was this big transition in your life and you became Martine.

MR: Correct.

CA: So tell me, how did that happen?

MR: It happened in consultation with Bina and our four beautiful children, and I discussed with each of them that I felt my soul was always female, and as a woman, but I was afraid people would laugh at me if I expressed it, so I always kept it bottled up and just showed my male side.

And each of them had a different take on this. Bina said, “I love your soul, and whether the outside is Martin and Martine, it doesn’t matter to me, I love your soul.”

My son said, “If you become a woman, will you still be my father?” And I said, “Yes, I’ll always be your father, and I’m still his father today.”

My youngest daughter did an absolutely brilliant five-year-old thing. She told people, “I love my dad and she loves me.” So she had no problem with a gender blending whatsoever.

CA: And a couple years after this, you published this book: The Apartheid of Sex.” What was your thesis in this book?

MR: My thesis in this book is that there are seven billion people in the world, and actually, seven billion unique ways to express one’s gender. And while people may have the genitals of a male or a female, the genitals don’t determine your gender or even really your sexual identity.

That’s just a matter of anatomy and reproductive tracts, and people could choose whatever gender they want if they weren’t forced by society into categories of either male or female the way South Africa used to force people into categories of black or white.

We know from anthropological science that race is fiction, even though racism is very real, and we now know from cultural studies that separate male or female genders is a constructed fiction. The reality is a gender fluidity that crosses the entire continuum from male to female.

CA: You yourself don’t always feel 100% female.

MR: Correct. I would say in some ways I change my gender about as often as I change my hairstyle.

 CA: (Laughs) Okay, now, this is your gorgeous daughter, Genesis. And I guess she was about this age when something pretty terrible happened.

MR: Yes, she was finding herself unable to walk up the stairs in our house to her bedroom, and after several months of doctors, she was diagnosed to have a rare, almost invariably fatal disease called pulmonary arterial hypertension.

CA: how did you respond to that?

MR: we first tried to get her to the best doctors we could. We ended up at Children’s National Medical Center in Washington, D.C. The head of pediatric cardiology told us that he was going to refer her to get a lung transplant, but not to hold out any hope, because there are very few lungs available, especially for children.

He said that all people with this illness died, and if any of you have seen the film “Lorenzo’s Oil,” there’s a scene when the protagonist kind of rolls down the stairway crying and bemoaning the fate of his son, and that’s exactly how we felt about Genesis.

CA: But you didn’t accept that as the limit of what you could do. You started trying to research and see if you could find a cure somehow.

 MR: Correct. She was in the intensive care ward for weeks at a time, and Bina and I would tag team to stay at the hospital while the other watched the rest of the kids, and when I was in the hospital and she was sleeping, I went to the hospital library.

I read every article that I could find on pulmonary hypertension. I had not taken any biology, even in college, so I had to go from a biology textbook to a college-level textbook and then medical textbook and the journal articles, back and forth, and eventually I knew enough to think that it might be possible that somebody could find a cure.

So we started a nonprofit foundation. I wrote a description asking people to submit grants and we would pay for medical research. I became an expert on the condition — doctors said to me, Martine, we really appreciate all the funding you’ve provided us, but we are not going to be able to find a cure in time to save your daughter.

However, there is a medicine that was developed at the Burroughs Wellcome Company that could halt the progression of the disease, but Burroughs Wellcome has just been acquired by Glaxo Wellcome. They made a decision not to develop any medicines for rare and orphan diseases, and maybe you could use your expertise in satellite communications to develop this cure for pulmonary hypertension.

 CA: So how on earth did you get access to this drug?

MR: I went to Glaxo Wellcome and after three times being rejected and having the door slammed in my face because they weren’t going to out-license the drug to a satellite communications expert, they weren’t going to send the drug out to anybody at all, and they thought I didn’t have the expertise, finally I was able to persuade a small team of people to work with me and develop enough credibility.

I wore down their resistance, and they had no hope this drug would even work, by the way, and they tried to tell me, “You’re just wasting your time. We’re sorry about your daughter.” But finally, for 25,000 dollars and agreement to pay 10 percent of any revenues we might ever get, they agreed to give me worldwide rights to this drug.

CA: And so you put this drug on the market in a really brilliant way, by basically charging what it would take to make the economics work.

MR: this really wasn’t a drug that I ended up — after I wrote the check for 25,000, and I said, “Okay, where’s the medicine for Genesis?” they said, “Oh, Martine, there’s no medicine for Genesis. This is just something we tried in rats.”

And they gave me, like, a little plastic Ziploc bag of a small amount of powder. They said, “Don’t give it to any human,” and they gave me a piece of paper which said it was a patent, and from that, we had to figure out a way to make this medicine.

A hundred chemists in the U.S. at the top universities all swore that little patent could never be turned into a medicine. If it was turned into a medicine, it could never be delivered because it had a half-life of only 45 minutes.

CA: And yet, a year or two later, you were there with a medicine that worked for Genesis.

 MR: the astonishing thing is that this absolutely worthless piece of powder that had the sparkle of a promise of hope for Genesis is not only keeping Genesis and other people alive today, but produces almost a billion and a half dollars a year in revenue.

10:58 (Applause)

CA: So here you go. So you took this company public, right? And made an absolute fortune. And how much have you paid Glaxo, by the way, after that 25,000?

MR: every year we pay them 10 percent of 1.5 billion, 150 million dollars, last year 100 million dollars. It’s the best return on investment they ever received. (Laughter)

CA: And the best news of all, I guess, is this.

MR: Yes. Genesis is an absolutely brilliant young lady. She’s alive, healthy today at 30. You see me, Bina and Genesis there. The most amazing thing about Genesis is that while she could do anything with her life, and believe me, if you grew up your whole life with people in your face saying that you’ve got a fatal disease, I would probably run to Tahiti and just not want to run into anybody again.

But instead she chooses to work in United Therapeutics. She says she wants to do all she can to help other people with orphan diseases get medicines, and today, she’s our project leader for all telepresence activities, where she helps digitally unite the entire company to work together to find cures for pulmonary hypertension.

CA: But not everyone who has this disease has been so fortunate. There are still many people dying, and you are tackling that too. How?

MR: There’s some 3,000 people a year in the United States alone, perhaps 10 times that number worldwide, who continue to die of this illness because the medicines slow down the progression but they don’t halt it.

The only cure for pulmonary hypertension, pulmonary fibrosis, cystic fibrosis, emphysema, COPD, what Leonard Nimoy just died of, is a lung transplant,

 Sadly, there are only enough available lungs for 2,000 people in the U.S. a year to get a lung transplant, whereas nearly a half million people a year die of end-stage lung failure.

CA: how can you address that?

MR: I conceptualize the possibility that just like we keep cars and planes and buildings going forever with an unlimited supply of building parts and machine parts, why can’t we create an unlimited supply of transplantable organs to keep people living indefinitely, and especially people with lung disease.

So we’ve teamed up with the decoder of the human genome, Craig Venter, and the company he founded with Peter Diamandis, the founder of the X Prize, to genetically modify the pig genome so that the pig’s organs will not be rejected by the human body and thereby to create an unlimited supply of transplantable organs. We do this through our company, United Therapeutics.

CA: So you really believe that within a decade, that this shortage of transplantable lungs maybe be cured, through these guys?

MR: I’m as certain of that as I was of the success that we’ve had with direct television broadcasting, Sirius XM. It’s actually not rocket science. It’s straightforward engineering away one gene after another. We’re so lucky to be born in the time that sequencing genomes is a routine activity, and the brilliant folks at Synthetic Genomics are able to zero in on the pig genome, find exactly the genes that are problematic, and fix them.

CA:  It’s not just long-lasting bodies that are of interest to you now. It’s long-lasting minds. And I think this graph for you says something quite profound. What does this mean?

MR: What this graph means, and it comes from Ray Kurzweil, is that the rate of development in computer processing hardware, firmware and software, has been advancing along a curve such that by the 2020s, as we saw in earlier presentations today, there will be information technology that processes information and the world around us at the same rate as a human mind.

CA: And so that being so, you’re actually getting ready for this world by believing that we will soon be able to, what, actually take the contents of our brains and somehow preserve them forever? How do you describe that?

MR: what we’re working on is creating a situation where people can create a mind file, and a mind file is the collection of their mannerisms, personality, recollection, feelings, beliefs, attitudes and values, everything that we’ve poured today into Google, into Amazon, into Facebook, and all of this information stored there will be able, in the next couple decades, once software is able to recapitulate consciousness, be able to revive the consciousness which is imminent in our mind file.

CA: Now you’re not just messing around with this. You’re serious. I mean, who is this?

MR: This is a robot version of my beloved spouse, Bina. And we call her Bina 48. She was programmed by Hanson Robotics out of Texas. There’s the centerfold from National Geographic magazine with one of her caregivers, and she roams the web and has hundreds of hours of Bina’s mannerisms, personalities. She’s kind of like a two-year-old kid, but she says things that blow people away, best expressed by perhaps a New York Times Pulitzer Prize-winning journalist Amy Harmon who says her answers are often frustrating, but other times as compelling as those of any flesh person she’s interviewed.

CA: And is your thinking here, part of your hope here, is that this version of Bina can in a sense live on forever, or some future upgrade to this version can live on forever?

MR: Yes. Not just Bina, but everybody. You know, it costs us virtually nothing to store our mind files on Facebook, Instagram, what-have-you. Social media is I think one of the most extraordinary inventions of our time, and as apps become available that will allow us to out-Siri Siri, better and better, and develop consciousness operating systems, everybody in the world, billions of people, will be able to develop mind clones of themselves that will have their own life on the web.

CA: So the thing is, Martine, that in any normal conversation, this would sound stark-staring mad, but in the context of your life, what you’ve done, some of the things we’ve heard this week, the constructed realities that our minds give, I mean, you wouldn’t bet against it.

MR: Well, I think it’s really nothing coming from me. If anything, I’m perhaps a bit of a communicator of activities that are being undertaken by the greatest companies in China, Japan, India, the U.S., Europe.

There are tens of millions of people working on writing code that expresses more and more aspects of our human consciousness, and you don’t have to be a genius to see that all these threads are going to come together and ultimately create human consciousness, and it’s something we’ll value.

There are so many things to do in this life, and if we could have a simulacrum, a digital doppelgänger of ourselves that helps us process books, do shopping, be our best friends, I believe our mind clones, these digital versions of ourselves, will ultimately be our best friends, and for me personally and Bina personally, we love each other like crazy.

Each day, we are always saying, like, “Wow, I love you even more than 30 years ago. And so for us, the prospect of mind clones and regenerated bodies is that our love affair, Chris, can go on forever. And we never get bored of each other. I’m sure we never will.

19:16 CA: I think Bina’s here, right?

MR: She is, yeah.

CA: Would it be too much, I don’t know, do we have a handheld mic? Bina, could we invite you to the stage? I just have to ask you one question. Besides, we need to see you.

Come and join Martine here. I mean, look, when you got married, if someone had told you that, in a few years time, the man you were marrying would become a woman, and a few years after that, you would become a robot — (Laughter) — how has this gone? How has it been?

Bina Rothblatt: It’s been really an exciting journey, and I would have never thought that at the time, but we started making goals and setting those goals and accomplishing things, and before you knew it, we just keep going up and up and we’re still not stopping, so it’s great.

CA: Martine told me something really beautiful, just actually on Skype before this, which was that he wanted to live for hundreds of years as a mind file, but not if it wasn’t with you.

BR: That’s right, we want to do it together. We’re cryonicists as well, and we want to wake up together.

20:35 CA: So just so as you know, from my point of view, this isn’t only one of the most astonishing lives I have heard, it’s one of the most astonishing love stories I’ve ever heard. It’s just a delight to have you both here at TED. Thank you so much.

Patsy Z and TEDxSKE shared a link.
The founder of Sirius XM satellite radio, Martine Rothblatt now heads up a drug company that makes life-saving medicines for rare diseases (including one drug…
ted.com|By Martine Rothblatt

Origins of life? Here we go again with new evidences

In the beginning, there were simple chemicals. And they produced amino acids that eventually became the proteins necessary to create single cells. And the single cells became plants and animals.

Recent research is revealing how the primordial soup created the amino acid building blocks, and there is widespread scientific consensus on the evolution from the first cell into plants and animals.

But it’s still a mystery how the building blocks were first assembled into the proteins that formed the machinery of all cells.

Now, two long-time University of North Carolina scientists – Richard Wolfenden, PhD, and Charles Carter, PhD – have shed new light on the transition from building blocks into life some 4 billion years ago.

“Our work shows that the close linkage between the of amino acids, the , and protein folding was likely essential from the beginning, long before large, sophisticated molecules arrived on the scene,” said Carter, professor of biochemistry and biophysics at the UNC School of Medicine.

“This close interaction was likely the key factor in the evolution from building blocks to organisms.”

Their findings, published in companion papers in the Proceedings of the National Academy of Sciences, fly in the face of the problematic “RNA world” theory, which posits that RNA – the molecule that today plays roles in coding, regulating, and expressing genes – elevated itself from the primordial soup of amino acids and cosmic chemicals to give rise first to short proteins called peptides and then to single-celled organisms.

Wolfenden and Carter argue that RNA did not work alone; in fact, it was no more likely that RNA catalyzed peptide formation than it was for peptides to catalyze RNA formation.

The finding adds a new layer to the story of how life evolved billions of years ago.

Its name was LUCA

The scientific community recognizes that 3.6 billion years ago there existed the last universal common ancestor, or LUCA, of all living things presently on Earth. It was likely a single-cell organism. It had a few hundred genes. It already had complete blueprints for DNA replication, protein synthesis, and RNA transcription.

It had all the basic components – such as lipids – that modern organisms have. From LUCA forward, it’s relatively easy to see how life as we know it evolved.

Before 3.6 billion years, however, there is no hard evidence about how LUCA arose from a boiling caldron of chemicals that formed on Earth after the creation of the planet about 4.6 billion years ago. Those chemicals reacted to form amino acids, which remain the building blocks of proteins in our own cells today.

“We know a lot about LUCA and we are beginning to learn about the chemistry that produced like amino acids, but between the two there is a desert of knowledge,” Carter said. “We haven’t even known how to explore it.”

The UNC research represents an outpost in that desert.

“Dr. Wolfenden established physical properties of the twenty amino acids, and we have found a link between those properties and the genetic code,” Carter said. “That link suggests to us that there was a second, earlier code that made possible the peptide-RNA interactions necessary to launch a selection process that we can envision creating the first life on Earth.”

Thus, Carter said, RNA did not have to invent itself from the . Instead, even before there were cells, it seems more likely that there were interactions between amino acids and nucleotides that led to the co-creation of proteins and RNA.

Complexity from simplicity

Proteins must fold in specific ways to function properly.

The first PNAS paper, led by Wolfenden, shows that both the polarities of the twenty amino acids (how they distribute between water and oil) and their sizes help explain the complex process of protein folding – when a chain of connected amino acids arranges itself to form a particular 3-dimensional structure that has a specific biological function.

Our experiments show how the polarities of amino acids change consistently across a wide range of temperatures in ways that would not disrupt the basic relationships between genetic coding and ,” said Wolfenden, Alumni Distinguished Professor of Biochemistry and Biophysics. This was important to establish because when life was first forming on Earth, temperatures were hot, probably much hotter than they are now or when the first plants and animals were established.

A series of biochemical experiments with amino acids conducted in Wolfenden’s lab showed that two properties – the sizes as well as the polarities of amino acids – were necessary and sufficient to explain how the amino acids behaved in folded proteins and that these relationships also held at the higher temperatures of Earth 4 billion years ago.

The second PNAS paper, led by Carter, delves into how enzymes called aminoacyl-tRNA synthetases recognized transfer ribonucleic acid, or tRNA. Those enzymes translate the genetic code.

Think of tRNA as an adapter,” Carter said. “One end of the adapter carries a particular amino acid; the other end reads the genetic blueprint for that amino acid in messenger RNA. Each synthetase matches one of the twenty amino acids with its own adapter so that the genetic blueprint in messenger RNA faithfully makes the correct every time.”

Carter’s analysis shows that the two different ends of the L-shaped tRNA molecule contained independent codes or rules that specify which amino acid to select. The end of tRNA that carried the amino acid sorted amino acids specifically according to size.

The other end of the L-shaped tRNA molecule is called the tRNA anticodon. It reads codons, which are sequences of three RNA nucleotides in genetic messages that select amino acids according to polarity.

Wolfenden and Carter’s findings imply that the relationships between tRNA and the physical properties of the – their sizes and polarities – were crucial during the Earth’s primordial era.

In light of Carter’s previous work with very small active cores of tRNA synthetases called Urzymes, it now seems likely that selection by size preceded selection according to polarity. This ordered selection meant that the earliest proteins did not necessarily fold into unique shapes, and that their unique structures evolved later.

Carter said, “Translating the genetic code is the nexus connecting pre-biotic chemistry to biology.”

He and Wolfenden believe that the intermediate stage of genetic coding can help resolve two paradoxes: how complexity arose from simplicity, and how life divided the labor between two very different kinds of polymers: proteins and nucleic acids.

“The fact that genetic coding developed in two successive stages – the first of which was relatively simple – may be one reason why life was able to emerge while the earth was still quite young,” Wolfenden noted.

An earlier code, which enabled the earliest coded peptides to bind RNA, may have furnished a decisive selective advantage. And this primitive system could then undergo a natural selection process, thereby launching a new and more biological form of evolution.

“The collaboration between RNA and peptides was likely necessary for the spontaneous emergence of complexity,” Carter added. “In our view, it was a peptide-RNA world, not an RNA-only world.”


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