September 7, 2011 in in_the_news
Largest Computer Simulation Peers into Dark Black Hole in Milky Way’s Centre
Toronto, Aug 24, 2011 /CNW/ – Telescopes can see light from distant galaxies; but it takes a supercomputer to see why the centre of our own is so dark.
The intense gravity near black holes makes for a violent, active region of space. Gas or stars that wander too near are torn apart, their energy released as X-rays. In the centre of the Milky Way, 26,000 light years away, is a black hole over four million times heavier than our Sun, but only modestly brighter. It’s eerily quiet — too quiet.
This mystery may have been solved by an international team of scientists lead by researchers at the Canadian Institute of Theoretical Astrophysics, and the University of Toronto Department of Astronomy and Astrophysics, in work to be published this month in Monthly Notices of the Royal Astronomical Society. The team used supercomputers at SciNet of the University of Toronto, performing the largest computer simulations ever performed in Canada, to test out their new theory.
“We’ve long thought that magnetic fields can choke off the flow of material into the black hole” says Prof. Ue-Li Pen of CITA. “Our earlier work suggested this, but then, it just wasn’t possible for a simulation to look at the huge range of lengths – from light years to light minutes – needed to track the hot gas as it falls all the way towards the black hole.”
“But our new methods, and SciNet, let us do just that,” added Dr. Bijia Pang. “We broke up the region of space near the black hole into 100 billion zones, and spread them over almost 18 thousands processors on SciNet’s largest cluster. This finally gave us the resolution we needed to test our model – we could see, with unprecedented accuracy,
the fields halting the turbulence and keeping the gas from falling in.”
The paper, “Numerical parameter survey of non-radiative black hole accretion: flow structure and variability of the rotation measure”, can be found online at http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2966.2011.18748.x/full
SciNet is Canada’s largest supercomputer centre, providing Canadian researchers with computational resources and expertise necessary to perform their research on scales not previously possible in Canada. SciNet powers work from the biomedical sciences and aerospace engineering to astrophysics and climate science. SciNet is part of Compute Canada, a national infrastructure for supercomputing-powered innovation, and is funded by CFI, NSERC, the Ontario Government, and the University of Toronto. More information is available at http://www.scinet.utoronto.ca.
SciNet HPC Consortium
Reprinted by The Wall Street Journal (http://online.wsj.com/article/PR-CO-20110908-904443.html), silobreaker.com, World News (wn.com), Business Wire, dig.com, digitaljournal.com, primeurmagazine.com