The Dark Attractor: What's Pulling the Milky Way Towards It at 14-Million MPH?

Astronomers have known for years that something unknown apears to be pulling our Milky Way and tens of thousands of other galaxies toward itself at a breakneck 22 million kilometers (14 million miles) per hour. But they couldn’t pinpoint exactly what, or where it is. A huge volume of space that includes the Milky Way and super-clusters of galaxies is flowing towards a mysterious, gigantic unseen mass named mass astronomers have dubbed "The Great Attractor," some 250 million light years from our Solar System. The Milky Way and Andromeda galaxies are the dominant structures in a galaxy cluster called the Local Group which is, in turn, an outlying member of the Virgo supercluster. Andromeda--about 2.2 million light-years from the Milky Way--is speeding toward our galaxy at 200,000 miles per hour...

EconoPhysics (On offer: laws of nature)

In yesterday's post I asked why economics doesn't have a few laws of nature that could prevent people from basing decisions on the financial equivalent of a perpetual motion machine. Enter the econophysicists, academics, ( usually physicists delving outside the field and not economists borrowing from physics ), who want to apply the rigorous mathematical methods of physics to understanding the economy. By modeling the economy as a collection of minor actors, like the molecules of gas, they hope to uncover how individual actions give rise to the emergent, large-scale phenomena that have sweeping effects—the booms and busts that take us by surprise.

Preserving the past for the future; Grant aids archival work at Institute. (Old Einstein pictures)

Princeton Township --The archivist lifted the pearl-gray cover off of an oversized folio of photographs recently found at the The National Medal of Science, Awarded by the President of the United States to Kurt Gödel in 1974, part of the Institute for Advanced Study archive collection, photographed on Friday, October 23, 2009. here. From beneath the protective tissue paper emerged a black and white photograph of the great, leonine face of Albert Einstein.

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.