gravitySimulator

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gravitySimulator is a novel supercomputer that incorporates special-purpose GRAPE hardware to solve the gravitational n-body problem. It is housed in the Center for Computational Relativity and Gravitation (CCRG) at the Rochester Institute of Technology. It became operational in 2005.

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The computer consists of 32 nodes, each of which contains a GRAPE-6A board ("mini-GRAPE") in a Peripheral Component Interconnect (PCI) slot.S. Harfst et al. (2007), [http://adsabs.harvard.edu/abs/2007NewA...12..357H Performance analysis of direct N-body algorithms on special-purpose supercomputers], New Astronomy, 12, 357 The GRAPE boards use pipelines to compute pairwise forces between particles at a speed of 130 Gflops.

The on-board memory of each GRAPE board can hold data for 128,000 particles, and by combining 32 of them in a cluster, a total of four million particles can be integrated, at sustained speeds of 4Tflops.[http://www.hpcwire.com/offthewire/17874824.html RIT's gravitySimulator Among the Fastest] {{webarchive|url=https://archive.today/20130126065150/http://www.hpcwire.com/offthewire/17874824.html |date=2013-01-26 }}, HPCwire, July 15, 2005

gravitySimulator is used to study the dynamical evolution of galaxies and galactic nuclei.P. Berczik et al. (2005), [http://adsabs.harvard.edu/abs/2006ApJ...642L..21B Efficient Merger of Binary Supermassive Black Holes in Nonaxisymmetric Galaxies], Astrophys. J., 642, L21A. Gualandris and D. Merritt (2008), [http://adsabs.harvard.edu/abs/2008ApJ...678..780G Ejection of Supermassive Black Holes from Galaxy Cores], Astrophys. J., 678, 780H. Perets et al. (2009), [https://arxiv.org/abs/0903.2912 Dynamical evolution of the young stars in the Galactic center], arXiv:0903.2912