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arXiv 2003.059142020-03-12hep-latcond-mat.str-elhep-phhep-th

Path integral contour deformations for noisy observables

William Detmold, Gurtej Kanwar, Michael L. Wagman, Neill C. Warrington

备注：: 7 pages, 2 figures
发表信息：: Phys. Rev. D 102, 014514 (2020)
DOI：: 10.1103/PhysRevD.102.014514

英文摘要：

Monte Carlo studies of many quantum systems face exponentially severe signal-to-noise problems. We show that noise arising from complex phase fluctuations of observables can be reduced without introducing bias using path integral contour deformation techniques. A numerical study of contour deformations for correlation functions in Abelian gauge theory and complex scalar field theory demonstrates that variance can be reduced by orders of magnitude without modifying Monte Carlo sampling.

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