Saved in:
Bibliographic Details
Main Authors: Lin, Shu, Bu, Yanyan, Lei, Chang
Format: Preprint
Published: 2023
Subjects:
Online Access:https://arxiv.org/abs/2301.06703
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916124289925120
author Lin, Shu
Bu, Yanyan
Lei, Chang
author_facet Lin, Shu
Bu, Yanyan
Lei, Chang
contents We present a systematic treatment of non-Gaussianity in stochastic systems using the Schwinger-Keldysh effective field theory framework, in which the non-Gaussianity is realized as nonlinear terms in the fluctuation field. We establish two stochastic formulations of the Schwinger-Keldysh effective field theory, with those nonlinear terms manifested as multiple non-Gaussian noises in the Langevin equation and as higher order diffusive terms in the Fokker-Planck equation. The equivalence of the stochastic formulations with the original Schwinger-Keldysh effective field theory is demonstrated with non-trivial examples for arbitrary non-Gaussian parameters. The stochastic formulations will be more flexible and effective in studying non-equilibrium dynamics. We also reveal an ambiguity when coarse-graining time scale and non-Gaussian parameters vanish simultaneously, which may be responsible for the unphysical divergence found in perturbative analysis.
format Preprint
id arxiv_https___arxiv_org_abs_2301_06703
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Non-Gaussianity from Schwinger-Keldysh Effective Field Theory
Lin, Shu
Bu, Yanyan
Lei, Chang
High Energy Physics - Theory
Statistical Mechanics
Nuclear Theory
We present a systematic treatment of non-Gaussianity in stochastic systems using the Schwinger-Keldysh effective field theory framework, in which the non-Gaussianity is realized as nonlinear terms in the fluctuation field. We establish two stochastic formulations of the Schwinger-Keldysh effective field theory, with those nonlinear terms manifested as multiple non-Gaussian noises in the Langevin equation and as higher order diffusive terms in the Fokker-Planck equation. The equivalence of the stochastic formulations with the original Schwinger-Keldysh effective field theory is demonstrated with non-trivial examples for arbitrary non-Gaussian parameters. The stochastic formulations will be more flexible and effective in studying non-equilibrium dynamics. We also reveal an ambiguity when coarse-graining time scale and non-Gaussian parameters vanish simultaneously, which may be responsible for the unphysical divergence found in perturbative analysis.
title Non-Gaussianity from Schwinger-Keldysh Effective Field Theory
topic High Energy Physics - Theory
Statistical Mechanics
Nuclear Theory
url https://arxiv.org/abs/2301.06703