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
Further Improvement of Qubit Lifetime for Quantum Computers
09.12.2016 | Forschungszentrum Jülich
Electron highway inside crystal
09.12.2016 | Julius-Maximilians-Universität Würzburg
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine