Stephen Wolfram: The Man Who Cracked The Code to Everything ...

..."The climax of the book is the principle of computational equivalence, which may as well be called "Wolfram's law." After hundreds of pages of laying groundwork, presenting case after case of visual examples where simple rules generate counterintuitively complex results, Wolfram concludes that this phenomenon is overwhelmingly commonplace - it's at the base of everything from morphology to traffic jams. Then he goes further, stating that once a system achieves a certain, easily attainable degree of complexity, it's reached the point of maximum complexity, as measured by the computation required to crank out the end result. Everything at that level of complexity - and that means almost everything you can think of, from human thought to rain hitting pavement - is exactly as complex as anything else."...

String theory pioneer succeeds Hawking in Lucasian role

One of the founders of string theory has been elected to replace Stephen Hawking as Cambridge University's Lucasian Professor of Mathematics. Professor Michael Green becomes the 18th holder of the professorship. Prof Green, who currently holds the John Humphrey Plummer Professorship of Theoretical Physics is one of the founders of string theory, generally regarded as the most successful candidate to date to unify quantum theory and general relativity, the two fundamental physical theories of the early twentieth century, and thereby formulate a consistent quantum theory of gravity.

Richard Dawkins: The world's most famous atheist

His new book, The Greatest Show on Earth: The Evidence for Evolution, arrives in the celebratory year that marks Darwin's 200th birthday and the 150th anniversary of the publication of the On the Origin of the Species.
 
Richard Dawkins home page

Douglas Eadline, Ph.D.: The Return of the Vector Processor

Before I dive into Fermi the GPU, I wanted to take a moment and pay tribute to Enrico Fermi the person — for whom the new GPU was named. For you young whippersnappers out there, Enrico Fermi is one of the giants of physics. He was instrumental in advancing physics on many fronts including quantum theory, nuclear and particle physics, and statistical mechanics ( a favorite subject of mine ). He had a rare combination of talent that allowed him to be both an excellent theorist and experimentalist. His legacy is legendary as he has an element named after him ( Fermium, a synthetic element created in 1952 ), a national lab ( the Fermi National Accelerator Lab ), and a class of particles that bare his name ( fermions ). No lightweight this Fermi fellow.

There has been no increase in solar irradiance since at least 1978

There has been work done reconstructing the solar irradiance record over the last century, before satellites were available. According to the Max Planck Institute, where this work is being done, there has been

no increase in solar irradiance since around 1940

This reconstruction does show an increase in the first part of the 20th century, which coincides with the warming from around 1900 until the 1940s. It's not enough to explain all the warming from those years, but it is responsible for a large portion. See this chart of observed temperature, modelled temperature, and variations in the major forcings that contributed to 20th century climate.

Historical Physicist Smackdown Explained: Electric Theory

So, who are the people in yesterday's poll about theoretical physicists, and why should you know them? Three of the four shared a Nobel Prize for developing quantum electrodynamics. In reverse order of voting: Julian Schwinger was an American physicist who came up with a very formal, mathematically rigorous way of describing the behavior of electrons interacting with light. This turns out to be a hard problem, because any attempt to calculate an electron's energy by simple, straightforward means ends up giving an infinite answer. Schwinger helped "renormalize" the theory, getting rid of the infinity with some elegant mathematics.

Deconstructing the electron

Explaining the behavior of interacting electrons in a solid is one of the long-standing problems in condensed matter. For most systems, the problem has been masterfully addressed by Landau, who showed that even though interactions can be very large, excitations behaving essentially as free fermions still exist in the system. The Landau Fermi-liquid theory allows sweeping the interactions under the rug and saying that the properties of many materials will be very similar to those of free electrons. However, this theory fails spectacularly when an electron gas is confined to one dimension. In that case, a completely new universality class appears, and the Fermi liquid turns into a Luttinger liquid.

download .pdf ( free )

Superheavy Element 114 Finally Re-created

By firing calcium isotopes into a plutonium target inside a particle accelerator, scientists at Lawrence Berkeley National Laboratory have finally confirmed the Russian discovery of the superheavy element 114. It wasn’t easy. It took more than a week of running the experiment to generate a measly two atoms of the stuff, which they reported in Physical Review Letters last week. It’s basic science at the outer limits of matter.

Pedagogía by Andrés Ibáñez

Pedagogía. Enseñar a enseñar. La falacia dice que  no sólo es necesario saber de algo, sino que también es necesario saber enseñarlo . Este principio o axioma casi místico se basa, como el amable lector habrá visto enseguida, en una presuposición no menos axial y mística, y no menos falaz que la anterior: A saber, que todos aquellos que no son pedagogos, no son ni pueden ser nunca buenos profesores.

Michelson–Morley experiment is best yet

Physicists in Germany have performed the most precise Michelson-Morley experiment to date,

confirming that the speed of light is the same in all directions

The experiment, which involves rotating two optical cavities, is about 10 times more precise than previous experiments – and a hundred million times more precise than Michelson and Morley's 1887 measurement.

U of S helps discover new family of superconductors

The superconductor family Tse discovered in conjunction with a number of international researchers is a group of hydrogen compounds known as molecular hydrides. Tse and graduate student Yansun Yao worked out the theoretical basis for the experiment as well as the key chemical structures involved, while German scientist Mikhail Eremets did the lab work.

First Solid Evidence for a Rocky Exoplanet

Mass and density of smallest exoplanet finally measured.

The longest set of HARPS measurements ever made has firmly established the nature of the smallest and fastest-orbiting exoplanet known, CoRoT-7b, revealing its mass as five times that of Earth's. Combined with CoRoT-7b's known radius, which is less than twice that of our terrestrial home, this tells us that the exoplanet's density is quite similar to the Earth's, suggesting a solid, rocky world. The extensive dataset also reveals the presence of another so-called super-Earth in this alien solar system.

First images of a carbon atom's electron clouds

The images were captured by  Igor Mikhailovskij 's team at the Kharkov Institute of Physics and Technology, Ukraine.

The $150 Space Camera: MIT Students Beat NASA On Beer-Money Budget

The two students ( from MIT, of course ) put together a low-budget rig to fly a camera high enough to photograph the curvature of the Earth. Instead of rockets, boosters and expensive control systems, they filled a weather balloon with helium and hung a styrofoam beer cooler underneath to carry a cheap Canon A470 compact camera. Instant hand warmers kept things from freezing up and made sure the batteries stayed warm enough to work.

HTML5 Canvas Cheat Sheet v. 1.1

Author: Jacob Seidelin

video – more than just a tag

This article is written by  Paul Rouget , Mozilla contributor and purveyor of extraordinary Open Web demos.

Starting with Firefox 3.5, you can embed a video in a web page like an image.

This means video is now a part of the document, and finally, a first class citizen of the Open Web. Like all other elements, you can use it with CSS and JavaScript. Let’s see what this all means …

Juan Aréchaga: Las revistas científicas españolas y el fraude bibliométrico

 Son muchos los problemas que continúan teniendo nuestras publicaciones para competir internacionalmente , dice el autor.

El reciente informe 2008 Journal Citation Reports Science Edition ( JCR, Institute for Scientific Information, Thomson Reuters, 2009 ) ofrece algunas novedades de interés, como el incremento, más bien escaso, de revistas españolas entre las 6.598 seleccionadas ( 0,56 % del total ) y un nuevo parámetro bibliométrico, denominado 5-Year Impact Factor, que mejora notablemente ediciones precedentes. Con toda seguridad, el último JCR ha sido espoleado por su nuevo competidor, conocido como SCImago Journal & Country Rank, desarrollado íntegramente en España sobre la base de datos SCOPUS de la multinacional holandesa Elsevier. Así, este repertorio amplía su análisis ya a  16.033 revistas científicas y, entre ellas, 227 ( 1,4 % ) españolas...¡ No hay nada mejor que la competencia para renovar productos y servicios ! Pero, también, el 2008JCR dedica un espacio importante al tema de las auto-referencias ( no confundir con las autocitas de los propios autores, que esto es harina de otro costal ), un aspecto que suele pasar desapercibido para muchos, pero que merece una especial atención por su trascendencia en España.

The uncalculability of electron systems

The electric and magnetic properties of solids are impossible to calculate exactly: The complex interactions of the many electrons which underly these phenomena cannot be computed even by the most powerful classical computers. Here, the central task is to determine the ground state of the electrons moving in the field of the positively charged nuclei. The most widely used method for treating such systems is Density Functional Theory, which reduces the many-body problem to a single particle interaction. As Dr. Norbert Schuch, scientist in the theory division of Prof. Ignacio Cirac at the Max Planck Institute of Quantum Optics in Garching, and Prof. Frank Verstraete from the University of Vienna, report in Nature Physics ( DOI: 10.1038/NPHYS1370 ), there exist however fundamental limitations to the applicability of this theory. The scientists succeeded by using methods developed in Quantum Information Theory, demonstrating that these methods can give deep insights beyond the development of quantum computers.

Physicist Proposes Solution to Arrow-of-Time Paradox

The laws of physics, which describe everything from electricity to moving objects to energy conservation, are time-invariant. That is, the laws still hold if time is reversed. However, this time reversal symmetry is in direct contrast with everyday phenomena, where  it’s obvious that time moves forward and not backward .

For example, when milk is spilt, it can’t flow back up into the glass, and when pots are broken, their pieces can’t shatter back together. This irreversibility is formalized through the second law of thermodynamics, which says that entropy always increases or stays the same, but never decreases. This contrast has created a reversibility paradox, also called  Loschmidt’s paradox , which scientists have been trying to understand since Johann Loschmidt began considering the problem in 1876. Scientists have proposed many solutions to the conundrum, from trying to embed irreversibility in physical laws to postulating low-entropy initial states.

IBM eyes molecule 'anatomy' for future computers

IBM scientists have imaged the chemical structure of an individual molecule, increasing the possibility for creating electronic building blocks on the atomic and molecular scale.

Scientists In Zurich, Switzerland, have, for the first time, imaged the "anatomy," or chemical structure, of an individual molecule with "unprecedented" resolution, using noncontact atomic force microscopy (AFM), IBM said Thursday. Resolving individual atoms within a molecule has been a long-standing goal of surface microscopy, according to the computer company, which has a research and development program dating back to 1945.