English

A Generic Solution of Fermion Sign Problem

Computational Physics 2022-06-01 v6 Strongly Correlated Electrons

Abstract

The fermion sign problem, the biggest obstacle in quantum Monte Carlo calculations, is completely solved in this paper. Here, we find a strategy, in which the contribution from those negative-weighted paths is thoroughly cancelled or replaced by some positive-weighted paths. The crucial point lies on the Feynman path integral formula proposed in our group, which allows us to deeply analyze the Boltzmann weight of each path. Through mathematical proof, we demonstrate that physical quantities can be exactly calculated within a specific kind of paths, which have positive the Boltzmann weight. With this finding, a new Monte Carlo method is proposed, in which the fermion sign problem is absent. As an example, the current method is applied to the two-dimensional Hubbard model, and the results do manifest the correctness.

Keywords

Cite

@article{arxiv.2203.04070,
  title  = {A Generic Solution of Fermion Sign Problem},
  author = {J. Wang and D. Y. Sun},
  journal= {arXiv preprint arXiv:2203.04070},
  year   = {2022}
}

Comments

24 pages, 4 figures

R2 v1 2026-06-24T10:05:58.717Z