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arXiv · 1305.6325

Multi-core computation of transfer matrices for strip lattices in the Potts model

Cristobal A. Navarro·Fabrizio Canfora·Nancy Hitschfeld Kahler
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Abstract

The transfer-matrix technique is a convenient way for studying strip lattices in the Potts model since the compu- tational costs depend just on the periodic part of the lattice and not on the whole. However, even when the cost is reduced, the transfer-matrix technique is still an NP-hard problem since the time T(|V|, |E|) needed to compute the matrix grows ex- ponentially as a function of the graph width. In this work, we present a parallel transfer-matrix implementation that scales performance under multi-core architectures. The construction of the matrix is based on several repetitions of the deletion- contraction technique, allowing parallelism suitable to multi-core machines. Our experimental results show that the multi-core implementation achieves speedups of 3.7X with p = 4 processors and 5.7X with p = 8. The efficiency of the implementation lies between 60% and 95%, achieving the best balance of speedup and efficiency at p = 4 processors for actual multi-core architectures. The algorithm also takes advantage of the lattice symmetry, making the transfer matrix computation to run up to 2X faster than its non-symmetric counterpart and use up to a quarter of the original space.

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Cristobal A. Navarro, Fabrizio Canfora, Nancy Hitschfeld Kahler. 2013-05-27. Multi-core computation of transfer matrices for strip lattices in the Potts model. https://doi.org/10.1109/hpcc.and.euc.2013.27

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