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Wednesday, April 24, 2013

Brontosaurus Found on Pluto!


Brian Switek in his charming "My Beloved Brontosaurus", reminds us that Brontosaurus never existed! All those kids in love with this monster, are no different than Unicorn fans.

Pluto is still there, but now we call it a dwarf planet not a planet.

What does "Brontosaurus Found on Pluto" mean?

It means, that our mind builds stories, we all need to feel under control knowing everything.

By the way: Information Exists!

Now; that is a title for another note.

Sunday, April 21, 2013

Sidney Coleman and Lee Smolin

Coleman

Smolin

I was lucky to be in the Cambridge area for the 1982- 1983 academic year. I was visiting Hung Cheng on a postdoctoral capacity. My PhD thesis, under Robert Sugar from UCSB,  is based on his work with T.T. Wu on the Expanding Proton. During that year I heard Coleman talk, on the principle of physical constants selection. I did not meet Smolin, but he has kept the flame burning. I read his book "The Life of the Cosmos", and now I am reading his newest book, "Time Reborn".

Independently of them, I have been thinking for a long time, that physical laws have to evolve. I believe that an absolute time is incompatible with most of modern scientific thought in physics. To avoid an infinite regress, Smolin, asks if black holes produce new sets of fundamental constants each time around, thus giving birth to a new universe, countless times. Some kind of universal adiabatical principle would separate time scales, like the Longue durée of the French Annals group. Just like geologist had trouble coming to terms with a rapidly changing plate tectonics, physicists have had trouble with the concept of changing laws of physics.

Finally, I recently read "The Physics of Wall Street", by James Owen Weatherall, where he explains the use of Gauge Theories in Economics.

It is reassuring that more and more people, are coming along to this set of ideas, if nothing else, I do not feel so much as an odd ball.

Saturday, April 13, 2013

Puebla

On Jorg Tofte Jebsen, and George Francis Rayner Ellis

J. T. Jebsen

George F.R. Ellis

Professor Ellis just sent an important paper to the arXiv.

There is a paper on the misnomer "Birkhoff's Theorem", here.

I  tell a personal story here.

I was born in Mexico City, my interest in Physics was inspired by Professor Mario Vázquez Reyna, of the Escuela Superior de Ingeniería Mecánica y Eléctrica, ESIME. Neither Professor Vázquez, nor Jebsen, and I am afraid, Ellis as well, have received their due respect in world science.

I first found out about Ellis studying his book, The Large Space Structure of Space-Time.  I studied this book in Puebla, Mexico, with my friend Juan Julián Rivadeneyra Pérez. I thought Ellis was a professor somewhere in England, it was a surprise to find him in South Africa. Following Birkhoff's path through Mexico, I found my professor's name, since he was one of the first Mexicans, to work in Modern Physics. Birkhoff did not know of Jebsen's Theorem, because Jebsen died young in Europe, afflicted with tuberculosis. Associated with Birkhoff in Mexico, there are other important names. Alberto Barajas, Carlos Graef Fernández, and Manuel Sandoval Vallarta. I had the good fortune of meeting some of them, as well as Graef's collaborator, Eduardo Piña Garza.

Only when conditions are sufficient, great talents flourish.

[1304.3253] Variations on Birkhoff's theorem

[1304.3253] Variations on Birkhoff's theorem:

"The relation between the expanding universe and local vacuum solutions, such as that for the Solar System, is crucially mediated by Birkhoff's theorem. Here we consider how that relation works, and give generalizations of Birkhoff's theorem when there are geometric and matter and perturbations. The issue of to what degree dark matter might influence the solar system emerges as a significant question"

'via Blog this'

Friday, April 12, 2013

Packed Planetary Systems and Atomic Model: "Motion has to fit,so it can last"

The Packed Planetary Systems (PPS) hypothesis states that:

"planetary systems form in such a way that the system could not support additional planets between the orbits of the existing ones, the gap would be expected to host a planet."

The atomic model obtained by the rules of Quantum Mechanics, produces a similar result. In one case, it has to do with the wave character of matter, in the other with stability theory in classical mechanics. There are general patterns of motion. The connecting principle may be stability. Adrian Bejan discovered the Constructal Theory: Flow is such that next time around, flow is easier. The code is in Newton's Mechanics, and Quantum Mechanics, uses waves to express this fundamental stability. Motion has to fit,so it can last.

From 1304.3341 we get:

"The PPS hypothesis suggests that the majority of systems will be near the edge of dynamical instability. That is, undetected planets will occupy a stable region and will tend to bring the system closer to (but not over the edge of) instability."

Lev's


Mary's


Wednesday, April 3, 2013

Years Later


Years Ago


Son


Mother and Siblings

Daughter and her Cousins

North Korean Threat

The recent tsunami in Japan made it possible to measure the antineutrinos coming from inside Earth. Read article here.  This is a fascinating story in itself, 38% of the energy fueling plate tectonics, and the Earth's magnetic field, comes from radioactivity in the Earth's interior, nevertheless I write here about the North Korean Nuclear Threat.

Reading the article above, I realized that South Korea uses a considerable amount of nuclear technology. To my unschooled mind, I do not see differences between the North and South Koreans. They share History, and a small Demilitarized Zone. It stands to reason that the North can pose a Nuclear Threat.

You don't need a weatherman to know which way the wind blows!

Tuesday, April 2, 2013

Werner R. Loewenstein



The radio was on in the background when I became aware of some vaguely familiar chords. As I began to listen more intently, a few swells of harmony pushed a button somewhere: Bach, the chorale “Out of the Deep,” the faint final accords.

I hadn’t heard that piece in decades. But as a teenager I had sung it in the school choir. Hearing those notes, I remembered the music and words of the entire chorale, as well as the withering look of the conductor when I missed my cue . . . and yes, the face of that girl in the choir I had fancied.

A melody, a face, the sounds of rushing wind, the smell of honey- suckle, the touch of a hand long still—all this we can perceive with the mind’s eye. We see, we hear, we feel, we remember, we are aware.

But what precisely do we mean when we say, “We are aware of something”? What is this peculiar state, at once so utterly familiar and so bewilderingly mysterious, that we call consciousness? What is its mechanism?

I put it like that point blank, to show from the start the tenor of the way and hold implicitly forth the expectation that consciousness has a physics explanation. Such a prospect may be shocking to some. That our mind and perceptions, our joys and sorrows, our memories, our sense of self, or worse, the glittering jewel of human intellect, thought, could be reduced to physics terms, may be a blow to one’s self-esteem. But it is really no more so than anything evolutionary—Darwinian schemes always step on the peacock tail.

In any case, that prospect should no longer be as shocking as it might have been, say, 20 years ago. In the meantime, the neurosciences have advanced on a broad front, only to bolster reductionist aspirations. The advances have held up the mirror to the brain, its intricate web of a trillion neurons, letting us see in detail as never before the stream of information that nurses our perceptions and the information processing that precedes them.

I wrote this book in an attempt to make these advances accessible to a wide spectrum of readers. I center on the information processing that takes place at the sensory periphery of the brain and at the brain cortex and examine it in the light of information theory. I have been fortunate that in the past few years there has been a major breakthrough in an offspring of that theory, quantum computation; the most spectacular advances happened just as I penned the last three chapters. So I was able to view the sensory information processing in this new light, especially the parallel processing that is the hallmark of the cognitive brain. That processing is the antecedent of consciousness and is exquisitely sensitive and fast, offering a target to test one’s reductionist mettle.

I originally intended to limit my story to the brain’s sensory periphery, to the capture and transfer of information at sensory receptors, a field I had worked in early in my career. But as I went on with the story, my leading characters, a set of talented biological molecules, started to develop wills of their own and did things quite different from those I had planned for them. Well, I should have been forewarned. Those are molecules operating by the strange rules of quantum logic. And in no time they took over the brain’s ground floor, the quantum bottom, presenting a tableau in which the boundaries between biology and physics vanished into thin air. That was a sight I could not resist. So this became a book on the sensory brain outright.

The book is written for the general reader with an interest in science. No specialized knowledge of biology, physics, or information theory is assumed in advance. With the general reader in mind, I have dispensed with mathematical apparatus. The few equations I used are tucked away in a footnote and the appendix. But the reader who wishes to skip them will not lose the thread of the book; the concepts they embody are explained in plain language along the way.

I have taken the liberty to personify throughout the book the process of biological evolution. I hope the reader won’t mind. Such a personification comes naturally if one looks at things from the information angle. It simplifies the narrative of an evolutionary process that is rare, if not unique, in the physics universe, where the good throws of the dice needn’t be repeated over and over again—an evolutionary process that generates its own information repository to progressively reduce the element of chance.

It may be surprising that in a book on brain and mind there should appear more physicists than biologists. This merely reflects the fact that the mind is frontier territory. Indeed, it is not at all uncommon in biological history to find physical scientists at the leading edges. Even Darwin, contrary to popular belief, was originally not a biologist, or at least he didn’t think of himself as one when he set out on the voyage of the Beagle: “I a geologist have illdefined [sic] notion of land covered with ocean, former animals, slow force cracking surface . . . ,” he wrote in his notebook. Nor did things change very much in that regard a century later, when modern biology was well on its way and molecular genetics was still a territory of uncharted wonders. Then again physicists were among the pioneers. And an encore is happening these days as the mind is becoming the new frontier. Indeed, the brain-mind problem, a subject that for centuries had been lying uneasily at the border of science and philosophy, may be the natural meeting ground between biologists and physicists.

Some years ago a group of students and colleagues of mine at Columbia University staged a mock biophysics symposium on my birthday. The “symposium” was an elaborate spoof on the vagaries of biophysics and the crowings of its practitioners. It was great fun, though much of it I have forgotten. But not the refrain of one of the ditties, and it has been haunting me ever since: “Biology is biology, and physics is physics, and never the twain shall meet.” If this book helps to sink that refrain into oblivion, that is the best I would ask for.