University of Chicago physicists have succeeded in creating a vortex knot—a feat akin to tying a smoke ring into a knot. Linked and knotted vortex loops have existed in theory for more than a century, but creating them in the laboratory had previously eluded scientists.
Vortex knots should, in principle, be persistent, stable phenomena. “The unexpected thing is that they’re not,” said Dustin Kleckner, a postdoctoral scientist at UChicago’s James Franck Institute. “They seem to break up in a particular way. They stretch themselves, which is a weird behavior.” (more…)
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…)
Studies by Berkeley Lab scientists of electron beam quality in laser plasma accelerators include novel tests for slice-energy spread
Part Two: Slicing through the electron beam
Wim Leemans of Berkeley Lab’s Accelerator and Fusion Research Division heads LOASIS, the Laser and Optical Accelerator Systems Integrated Studies, an oasis indeed for students pursuing graduate studies in laser plasma acceleration (LPA). Among the most promising applications of future table-top accelerators are new kinds of light sources, in which their electron beams power free electron lasers.
“If our LPA electron bunches had good enough quality for free electron lasers – and were really only femtoseconds long – we should see a particular kind of radiation called coherent optical transition radiation, or COTR,” Leemans says. “So I assigned my doctoral student Chen Lin, a graduate of Peking University and now a postdoc there, to find it.” (more…)
*Nadella brings deep engineering and online services knowledge to $15 billion business*
REDMOND, Wash. — Feb. 9, 2011 — Microsoft Corp. today promoted Senior Vice President Satya Nadella to president of Microsoft’s Server and Tools Business.
“We’re already making strong traction across our Server and Tools Business by embracing cloud services,” said Microsoft Chief Executive Officer Steve Ballmer. “Satya has deep experience in both our server business and online services, which will help accelerate our momentum while setting the course to deliver the cloud computing scenarios of the future.” (more…)
Although the second quarter financial reports from both Microsoft and Yahoo! could bring ‘disappointment’ for the tech-concerned intellectuals, but something ‘optimism’ is peeping out of the clouds.
That’s the deal – the long waited ‘search and ad’ deal. 😉
