The work seeks to clarify what Massachusetts Institute of Technology researchers witnessed when in 2013 they named a mysterious phenomenon — an unusual long-lived wave traveling much more slowly than expected through a gas of cold atoms. They called this wave a "heavy soliton" and claimed it defied theoretical description.
But in one of the largest supercomputing calculations ever performed, UW physicists Aurel Bulgac and Michael Forbes and co-authors have found this to be a case of mistaken identity: The heavy solitons observed in the earlier experiment are likely vortex rings – a sort of quantum equivalent of smoke rings.
"The experiment interpretation did not conform with theory expectations," said Bulgac. "We had to figure out what was really happening there. It was not obvious it was one thing or another — thus it took a bit of police work."
A vortex ring is a doughnut-shaped phenomenon where fluids or gases knot and spin in a closed, usually circular loop. The physics of vortex rings is the same as that which gives stability to tornadoes, volcanic eruptions and mushroom clouds. (Dolphins actually create their own vortex rings in water for entertainment.)
"Using state-of-the-art computing techniques, we demonstrated with our simulation that virtually all aspects of the MIT results can be explained by vortex rings" said Forbes, an UW affiliate professor who in January became an assistant professor of physics at Washington State University.
He said the simulations they used "could revolutionize how we solve certain physics problems in the future," such as studying nuclear reactions without having to perform nuclear tests. As for neutron stars, he said the work also could lead to a better understanding of "glitches," or rapid increases in such a star's pulsation frequency, as this may be due to vortex interactions inside the star.
"We are now at a cusp where our computational capabilities are becoming sufficient to shed light on this longstanding problem. This is one of our current directions of research — directly applying what we have learned from the vortex rings," Forbes said.
The computing work for the research — one of the largest direct numerical simulations ever — was performed on the supercomputer Titan, at the Oak Ridge Leadership Computing Facility in Tennessee, the nation's most powerful computer for open science. Work was also performed on the UW's Hyak high-performance computer cluster.
Bulgac and Forbes published their findings in a January issue of Physical Review Letters. Co-authors are Kenneth Roche of the Pacific Northwest National Laboratory and the UW; Gabriel Wlaz³owski of the Warsaw University of Technology and the UW; and Michelle Kelley of the University of Illinois at Urbana-Champaign.The research was funded by grants number DE-FG02-97ER41014 and
For more information, contact Bulgac at 206-685-2988, or email@example.com; or Forbes at 509-335-6125 or firstname.lastname@example.org.
Peter Kelley | Newswise
Enhancing the quantum sensing capabilities of diamond
23.11.2017 | The Hebrew University of Jerusalem
Quantum optics allows us to abandon expensive lasers in spectroscopy
22.11.2017 | Lomonosov Moscow State University
Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
23.11.2017 | Information Technology
23.11.2017 | Physics and Astronomy
23.11.2017 | Life Sciences