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Natural 3D Counterpart to Graphene Discovered

By Guest PostJanuary 26, 2014Science2d, 2d dirac fermions, 3d version, 3dtds, 3dtds systems, advanced light source, als, antiparticle, berkeley lab, bo zhou, bulk electrons behave, chinese academy, dirac semi metal, electron mobility, graphene, natural 3d counterpart, quantum matter, sciences, sheets of carbon, three-dimensional, topological, topological insulators, velocity, yulin chen, zahid hussain, zhongkai liu

Researchers at Berkeley Lab’s Advanced Light Source Find New Form of Quantum Matter

The discovery of what is essentially a 3D version of graphene – the 2D sheets of carbon through which electrons race at many times the speed at which they move through silicon – promises exciting new things to come for the high-tech industry, including much faster transistors and far more compact hard drives. A collaboration of researchers at the U.S Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) has discovered that sodium bismuthide can exist as a form of quantum matter called a three-dimensional topological Dirac semi-metal (3DTDS). This is the first experimental confirmation of 3D Dirac fermions in the interior or bulk of a material, a novel state that was only recently proposed by theorists. (more…)

UCLA scientists explain the formation of unusual ring of radiation in space

By Guest PostSeptember 29, 2013Scienceadam kellerman, alexander drozdov, dmitriy subbotin, earth, explain, formation, hazardous, high energy electrons, highly charged particles, jack eddy fellowship, ksenia orlova, kyung chan kim, MIT, model, NASA, plasma waves, President Obama, radiation belts, ring of radiation, russia, simulation, skolkovo institute, Space, third radiation ring, ucla scientists, ultra relativistic electrons, unusual, van allen, velocity, yuri shprits

Since the discovery of the Van Allen radiation belts in 1958, space scientists have believed these belts encircling the Earth consist of two doughnut-shaped rings of highly charged particles — an inner ring of high-energy electrons and energetic positive ions and an outer ring of high-energy electrons.

In February of this year, a team of scientists reported the surprising discovery of a previously unknown third radiation ring — a narrow one that briefly appeared between the inner and outer rings in September 2012 and persisted for a month. (more…)

How Computers Push on the Molecules They Simulate

By Guest PostJanuary 9, 2013Scienceacceleration, albert einstein, algorithm, analytical results, artifacts, atoms and molecules, behavior, Berkeley, berkeley lab, calculation, california, california institute, chemical fuel, collide, computer method, conserve energy, david sivak, digital representation, digitize time, dna repair, driving force, effective friction, energy dense, equation, error, finite time steps, fluid, french physicist, gavin crooks, john chodera, langevin dynamics, model brownian motion, modeling molecular system, modern computer, molecular machines, molecular scale motion, molecule, momentum, natural system, nonequilibrium driving force, nonequilibrium statistical mechanics, particle, passage of time, paul langevin, photosynthesis, pollen grain, qb3, quantitative biosciences, quantum mechanics, real world, simulation, source, tenacious errors, theoretical method, thermal energy, toy models, university, velocity, water, water molecules

Berkeley Lab bioscientists and their colleagues decipher a far-reaching problem in computer simulations

Because modern computers have to depict the real world with digital representations of numbers instead of physical analogues, to simulate the continuous passage of time they have to digitize time into small slices. This kind of simulation is essential in disciplines from medical and biological research, to new materials, to fundamental considerations of quantum mechanics, and the fact that it inevitably introduces errors is an ongoing problem for scientists.

Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have now identified and characterized the source of tenacious errors and come up with a way to separate the realistic aspects of a simulation from the artifacts of the computer method. The research was done by David Sivak and his advisor Gavin Crooks in Berkeley Lab’s Physical Biosciences Division and John Chodera, a colleague at the California Institute of Quantitative Biosciences (QB3) at the University of California at Berkeley. The three report their results in Physical Review X. (more…)

How Galaxies Grow Up

By Guest PostOctober 20, 2012Scienceadam block, age, andromeda galaxy, astronomer, benjamin weiner, blue galaxies, california, computer program, computer simulation, deep2, emission line, galaxies, Galaxy, galaxy evolution, galaxy population, galaxy type, gas, grow up, hawaii, internal motion, keck telescopes, lick observatory, light years, m88 galaxy, massive system, Milky Way, mount lemmon, NASA, observational data, random motion, redshift survey, rotation speed, santa cruz, skycenter, spiral disk shape, star forming galaxies, susan kassin, ua, universe, university, velocity

A study of 544 star-forming galaxies shows that disk galaxies like our own Milky Way reached their current state as orderly rotating pinwheels much later than previously thought, long after much of the universe’s star formation had ceased.

Galaxies are in no hurry to grow up, a team of astronomers has discovered. A comprehensive study of hundreds of galaxies observed by the Keck telescopes in Hawaii and NASA’s Hubble Space Telescope has revealed an unexpected pattern of change that extends back 8 billion years, or more than half the age of the universe.

Researchers say the distant blue galaxies they studied are gradually transforming into rotating disk galaxies like our own Milky Way. Until now, it had not been clear how a galaxy’s organization and internal motion change over time, said Benjamin Weiner, assistant astronomer at the UA Steward Observatory and co-author of the paper describing the findings, which are published in The Astrophysical Journal. (more…)

Ribbeting Research

By Guest PostJuly 13, 2012Nature, Scienceacoustic difference, amphibians, amplexus, cocktail party problem, eardrum movement, eustachian tubes, female cope, frog ears, frogs, gray treefrog, hearing aids, jackhammer, mammalian ears, mammals, mark bee, mr right, study, university of minnesota, velocity

Studies of frogs may lead to better hearing aids

When Mark Bee talks to his 106-year-old grandmother alone, her two enormous hearing aids enable her to understand him well.

“But at a table at Thanksgiving, with everybody talking, the devices don’t do well,” says Bee, an associate professor of ecology, evolution and behavior at the University of Minnesota.

Her difficulty in a noisy situation is called the cocktail party problem, after the background babble that stymies many hearing-impaired people trying to pick out individual voices at a party. But in ponds all over the world, frogs handle a similar problem, and Bee hopes to learn enough about how they do it to put the principles to work helping people like his grandmother. (more…)

IBM Advances Big Data Analytics with Acquisition of Vivisimo

By Guest PostApril 25, 2012Technologyairbus, analyze, apache hadoop, arvind Krishna, big data, big data technology, cloudera, data, defense intelligence agency, ibm, ibm analytics, john kealey, navigation software, Pennsylvania, petabytes, pittsburgh, quintillion bytes, us air force, velocity, vivisimo, volume

Armonk, N.Y. – 25 Apr 2012: IBM today announced a definitive agreement to acquire Vivisimo, a leading provider of federated discovery and navigation software that helps organizations access and analyze big data across the enterprise. Vivisimo is a privately held company based in Pittsburgh, Pennsylvania. Financial terms were not disclosed.

Vivisimo software excels in capturing and delivering quality information across the broadest range of data sources, no matter what format it is, or where it resides. The software automates the discovery of data and helps employees navigate it with a single view across the enterprise, providing valuable insights that drive better decision-making for solving all operational challenges. (more…)

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