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arXiv · 2001.02258

Thermodynamically-Efficient Local Computation and the Inefficiency of Quantum Memory Compression

Samuel P. Loomis·James P. Crutchfield
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Abstract

Modularity dissipation identifies how locally-implemented computation entails costs beyond those required by Landauer's bound on thermodynamic computing. We establish a general theorem for efficient local computation, giving the necessary and sufficient conditions for a local operation to have zero modularity cost. Applied to thermodynamically-generating stochastic processes it confirms a conjecture that classical generators are efficient if and only if they satisfy retrodiction, which places minimal memory requirements on the generator. This extends immediately to quantum computation: Any quantum simulator that employs quantum memory compression cannot be thermodynamically efficient.

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Samuel P. Loomis, James P. Crutchfield. 2020-01-07. Thermodynamically-Efficient Local Computation and the Inefficiency of Quantum Memory Compression. https://doi.org/10.1103/physrevresearch.2.023039

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