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DOE OSTI · 1565247

2HOT: An improved parallel hashed oct-tree N-body algorithm for cosmological simulation

Warren, Michael S.
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Abstract

Here we report on improvements made over the past two decades to our adaptive treecode N-body method (HOT). A mathematical and computational approach to the cosmological N-body problem is described, with performance and scalability measured up to 256k (218) processors. We present error analysis and scientific application results from a series of more than ten 69 billion (40963) particle cosmological simulations, accounting for 4×1020 floating point operations. These results include the first simulations using the new constraints on the standard model of cosmology from the Planck satellite. Our simulations set a new standard for accuracy and scientific throughput, while meeting or exceeding the computational efficiency of the latest generation of hybrid TreePM N-body methods.

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BibTeXRIS

Warren, Michael S.. 2014-01-01. 2HOT: An improved parallel hashed oct-tree N-body algorithm for cosmological simulation. https://doi.org/10.3233/spr-140385

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