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arXiv · 1604.00651

A Direct Mapping of Max k-SAT and High Order Parity Checks to a Chimera Graph

Nicholas Chancellor·Stefan Zohren·Paul A. Warburton·Simon C. Benjamin·Stephen Roberts
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Abstract

We demonstrate a direct mapping of max k-SAT problems (and weighted max k-SAT) to a Chimera graph, which is the non-planar hardware graph of the devices built by D-Wave Systems Inc. We further show that this mapping can be used to map a similar class of maximum satisfiability problems where the clauses are replaced by parity checks over potentially large numbers of bits. The latter is of specific interest for applications in decoding for communication. We discuss an example in which the decoding of a turbo code, which has been demonstrated to perform near the Shannon limit, can be mapped to a Chimera graph. The weighted max k-SAT problem is the most general class of satisfiability problems, so our result effectively demonstrates how any satisfiability problem may be directly mapped to a Chimera graph. Our methods faithfully reproduce the low energy spectrum of the target problems, so therefore may also be used for maximum entropy inference.

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Nicholas Chancellor, Stefan Zohren, Paul A. Warburton, Simon C. Benjamin, Stephen Roberts. 2016-11-01. A Direct Mapping of Max k-SAT and High Order Parity Checks to a Chimera Graph. https://doi.org/10.1038/srep37107

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