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arXiv · 2510.26408

Feynman path sum approach for simulation of linear optics

Wagner F. Balthazar·Quinn M. B. Palmer·Alex. E. Jones·Jake F. F. Bulmer·Ernesto. F. Galvão
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Abstract

The Feynman path integral formalism has inspired the development of memory-efficient and parallelizable classical algorithms for simulating quantum computers. We adapt this approach for the calculation of probability amplitudes of linear-optical boson sampling experiments, which involve Fock-state inputs, linear optical circuits, and photo-detection at the output. We describe this simulation method and compare it with alternative approaches. Additionally, we implement a Linear-Optical Feynman Path simulator in open-source C code, enhancing its performance using tensor contraction techniques. Our method is benchmarked for low-depth linear optical circuits, where it offers advantages in runtime and memory efficiency.

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Wagner F. Balthazar, Quinn M. B. Palmer, Alex. E. Jones, Jake F. F. Bulmer, Ernesto. F. Galvão. 2025-10-30. Feynman path sum approach for simulation of linear optics. https://arxiv.org/abs/2510.26408

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