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A Parallel Processing Algorithm for Computing Short-Range Particle Forces with Inhomogeneous Particle Distributions

Robert C. Ferrell·Edmund Bertschinger
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Abstract

We present a computational algorithm for computing short range forces between particles. The algorithm has two distinguishing features. First, it is optimized for multi-processor computers, and will use as many processors as are available. Second, it is optimized for inhomogeneous, dynamic particle distributions; for any distribution the computational load is distributed evenly to all processors, and the communication time is less than 15\% of the total run time. In this talk we present our new algorithm. We developed the program for a grand-challenge problem in cosmology, simulation of the formation of large-scale structure in the universe. This simulation, run on the Thinking Machines Corporation CM-5, uses the particle-particle/particle-mesh (PPPM) \cite{hock_east} algorithm. The particle-particle phase is computed using the algorithm we describe in this paper. We discuss this and other applications.

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Robert C. Ferrell, Edmund Bertschinger. 1995-03-10. A Parallel Processing Algorithm for Computing Short-Range Particle Forces with Inhomogeneous Particle Distributions. https://arxiv.org/abs/astro-ph/9503042

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