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When Matter Melts

By Guest PostJune 27, 2011Scienceantiproton collisions, balance of matter and antimatter, bedangadas mohanty, berkeley lab, CERN, color force, critical point, distribution of ordinary matter, elemental constituents of matter, geneva, gluons, hadronic matter, hans georg ritter, heavy ions, India, kolkata, Large Hadron Collider, lattice theory, massive gold nuclei, neutrons, nu xu, phase diagrams, protons, qcd, quantum chromodynamics, quark gluon plasma, relativistic heavy ion collider, rhic, sourendu gupta, tata institute of fundamental research, universe, variable energy cyclotron centre, xiaofeng luo

*By comparing theory with data from STAR, Berkeley Lab scientists and their colleagues map phase changes in the quark-gluon plasma*

In its infancy, when the universe was a few millionths of a second old, the elemental constituents of matter moved freely in a hot, dense soup of quarks and gluons. As the universe expanded, this quark–gluon plasma quickly cooled, and protons and neutrons and other forms of normal matter “froze out”: the quarks became bound together by the exchange of gluons, the carriers of the color force.

“The theory that describes the color force is called quantum chromodynamics, or QCD,” says Nu Xu of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), the spokesperson for the STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at DOE’s Brookhaven National Laboratory. “QCD has been extremely successful at explaining interactions of quarks and gluons at short distances, such as high-energy proton and antiproton collisions at Fermi National Accelerator Laboratory. But in bulk collections of matter – including the quark-gluon plasma – at longer distances or smaller momentum transfer, an approach called lattice gauge theory has to be used.” (more…)

Just Four Percent of Galaxies Have Neighbors Like the Milky Way

By Guest PostMay 26, 2011Scienceanalyses of data, big bang, cdm, cold dark matter theory, computer model, formation of our galaxy, Galaxy, luminosity, magellanic clouds, Milky Way, nigel sharp, optical sky, risa wechsler, sdss, stanford university, universe

*Our home galaxy belongs to a rare subset among the billions that populate the cosmos*

How unique is the Milky Way?

To find out, a group of researchers led by Stanford University astrophysicist Risa Wechsler compared the Milky Way to similar galaxies and found that just four percent are like the galaxy Earth calls home. (more…)

NASA Telescope Helps Confirm Nature of Dark Energy

By Guest PostMay 20, 2011Science3 d map, albert einstein, anglo australian telescope, australia, big bang, caltech, chris blake, christopher martin, constant force, cosmic time, dark energy, dark matter, galaxies, galaxy evolution explorer, gravitational attractions, gravity, how dark energy works, jon morse, melbourne, NASA, siding spring mountain, swinburne university of technology, universe

PASADENA, Calif. — A five-year survey of 200,000 galaxies, stretching back seven billion years in cosmic time, has led to one of the best independent confirmations that dark energy is driving our universe apart at accelerating speeds. The survey used data from NASA’s space-based Galaxy Evolution Explorer and the Anglo-Australian Telescope on Siding Spring Mountain in Australia.

The findings offer new support for the favored theory of how dark energy works — as a constant force, uniformly affecting the universe and propelling its runaway expansion. They contradict an alternate theory, where gravity, not dark energy, is the force pushing space apart. According to this alternate theory, with which the new survey results are not consistent, Albert Einstein’s concept of gravity is wrong, and gravity becomes repulsive instead of attractive when acting at great distances. (more…)

Why Some Planets Orbit the Wrong Way; Extrasolar Insights into Our Solar System

By Guest PostMay 14, 2011Scienceastronomers, astrophysicist, beverly berger, eccentric, extrasolar planets, extrasolar systems, frederic a rasio, gravitational coupling, gravitational perturbations, hot jupiter, jupiter's orbit, jupiters, lynette cook, NASA, national science foundation, orbital mechanics, planetary system, planets, solar system, star formation, universe

More than 500 extrasolar planets–planets that orbit stars other than the sun–have been discovered since 1995. But only in the last few years have astronomers observed that in some of these systems, the star is spinning one way and the planet is orbiting that star in the opposite direction.

“That’s really weird, and it’s even weirder because the planet is so close to the star,” said Frederic A. Rasio, a theoretical astrophysicist at Northwestern University. “How can one be spinning one way and the other orbiting exactly the other way? It’s crazy. It so obviously violates our most basic picture of planet and star formation.” (more…)

Measuring the Distant Universe in 3-D

By Guest PostMay 7, 2011Science3 d map, absorption, anže slosar, apache point observatory, bao, baryon acoustic oscillation, baryon oscillation, baryon oscillation spectroscopic survey, berkeley lab, bill carithers, BOSS, centers of galaxies, dark energy, david schlegel, james rich, lyman alpha forest, map intergalactic hydrogen gas, new mexico, of light years, precision tool, quasars, red galaxies, redshift, sdss, sloan digital sky survey, sloan telescope, spectrum, supermassive black holes, universe, wiggly structure

*Berkeley Lab-led BOSS proves it can do the job with quasars*

The biggest 3-D map of the distant universe ever made, using light from 14,000 quasars — supermassive black holes at the centers of galaxies many billions of light years away — has been constructed by scientists with the third Sloan Digital Sky Survey (SDSS-III).

The map is the first major result from the Baryon Oscillation Spectroscopic Survey (BOSS), SDSS-III’s largest survey, whose principal investigator is David Schlegel of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). The huge new map was presented at the April meeting of the American Physical Society in Anaheim, CA, by Anže Slosar of Brookhaven National Laboratory. (more…)

WISE Delivers Millions of Galaxies, Stars, Asteroids

By Guest PostApril 17, 2011Scienceastronomers, blue star, celestial objects, colorful images of the cosmos, earth, edward wright, entire sky, fengchuan liu, galaxies, infrared wavelengths, nasa. wide field infrared survey explorer, polar orbit, roc cutri, solar system, star forming complexes, universe, wise, zeta ophiuchi

Astronomers across the globe can now sift through hundreds of millions of galaxies, stars and asteroids collected in the first bundle of data from NASA’s Wide-field Infrared Survey Explorer (WISE) mission.

“Starting today thousands of new eyes will be looking at WISE data, and I expect many surprises,” said Edward (Ned) Wright of UCLA, the mission’s principal investigator. (more…)

Enhancing the Magnetism: Berkeley Researchers Find Enhanced and Controllable Magnetization in Unique Bismuth Ferrite Films

By Guest PostMarch 27, 2011Sciencebfo, bismuth ferrite, dick tracy, domain walls, helen he, information age, john heron, magnetism, magnetoelectronic, multiferroic property, nanoscale, partial relaxation, qing, ramamoorthy ramesh, rhombohedral phases, spintronic devices, spontaneous magnetism, spontaneous magnetization, universe, ying hao chu

“The nation that controls magnetism will control the universe,” famed fictional detective Dick Tracy predicted back in 1935. Probably an overstatement, but there’s little doubt the nation that leads the development of advanced magnetoelectronic or “spintronic” devices is going to have a serious leg-up on its Information Age competition. A smaller, faster and cheaper way to store and transfer information is the spintronic grand prize and a key to winning this prize is understanding and controlling a multiferroic property known as “spontaneous magnetization.”

Now, researchers with the U.S. Department of Energy (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) have been able to enhance spontaneous magnetization in special versions of the popular multiferroic material bismuth ferrite. What’s more, they can turn this magnetization “on/off” through the application of an external electric field, a critical ability for the advancement of spintronic technology. (more…)

Herschel Measures Dark Matter for Star-Forming Galaxies

By Guest PostFebruary 21, 2011Sciencealexandre amblard, asantha cooray, astronomers, dark matter, distant galaxies, european space agency, exotic substance, Galaxy, herschel, herschel space observatory, jamie bock, longer wavelength infrared light, massive galaxies, Milky Way, Nature, star forming galaxies, stars, telescope, universe, william danchi

PASADENA, Calif. — The Herschel Space Observatory has revealed how much dark matter it takes to form a new galaxy bursting with stars. Herschel is a European Space Agency cornerstone mission supported with important NASA contributions.

The findings are a key step in understanding how dark matter, an invisible substance permeating our universe, contributed to the birth of massive galaxies in the early universe. (more…)

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