2016/10/25 by Evgeny Polyakov, A. N. Rubtsov, Polyakov, Evgeny A. +1
Computer Science · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum Physics (quant-ph)
paper · pdf · doi:10.48550/arxiv.1610.08964
openalex publication_date 2016/10/25 · openalex created_date 2022/09/13 · openalex updated_date 2026/07/28
The derivation of path integrals is reconsidered. It is shown that the\nexpression for the discretized action is not unique, and the path integration\ndomain can be deformed so that at least Gaussian path integrals become\nprobabillistic. This leads to a practical algorithm of sign-problem-free Monte\nCarlo sampling from the Gaussian path integrals. Moreover, the dynamical\ninfluence of Gaussian quantum system (the bath) on any other quantum system can\nbe exactly represented as interaction with classical non-Markovian noise. We\ndiscuss the relation of these findings to the Bell's theorem and the Feynman's\nconjecture on the exponential complexity of the classical simulation of quantum\nsystems. In Feynman's path integral we have quasiprobability distributions for\ntrajectories, and in analitycally continued path integrals we have probability\ndistributions for quasitrajectories.\n