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arXiv · 2005.14075

Quantum self-learning Monte Carlo with quantum Fourier transform sampler

Katsuhiro Endo·Taichi Nakamura·Keisuke Fujii·Naoki Yamamoto
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Abstract

The self-learning Metropolis-Hastings algorithm is a powerful Monte Carlo method that, with the help of machine learning, adaptively generates an easy-to-sample probability distribution for approximating a given hard-to-sample distribution. This paper provides a new self-learning Monte Carlo method that utilizes a quantum computer to output a proposal distribution. In particular, we show a novel subclass of this general scheme based on the quantum Fourier transform circuit; this sampler is classically simulable while having a certain advantage over conventional methods. The performance of this "quantum inspired" algorithm is demonstrated by some numerical simulations.

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Katsuhiro Endo, Taichi Nakamura, Keisuke Fujii, Naoki Yamamoto. 2020-05-28. Quantum self-learning Monte Carlo with quantum Fourier transform sampler. https://doi.org/10.1103/physrevresearch.2.043442

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