TY - JOUR

T1 - Kinetic Theory of Boson Gas

AU - Honkonen, J.

AU - Komarova, M. V.

AU - Molotkov, Yu G.

AU - Nalimov, M. Yu

N1 - Publisher Copyright: © 2019, Pleiades Publishing, Ltd. Copyright: Copyright 2019 Elsevier B.V., All rights reserved.

PY - 2019/9/1

Y1 - 2019/9/1

N2 - We construct a quantum kinetic theory of a weakly interacting critical boson gas using the expectation values of products of Heisenberg field operators in the grand canonical ensemble. Using a functional representation for the Wick theorem for time-ordered products, we construct a perturbation theory for the generating functional of these time-dependent Green’s functions at a finite temperature. We note some problems of the functional-integral representation and discuss unusual apparent divergences of the perturbation expansion. We propose a regularization of these divergences using attenuating propagators. Using a linear transformation to variables with well-defined scaling dimensions, we construct an infrared effective field theory. We show that the structure of the regularized model is restored by renormalization. We propose a multiplicatively renormalizable infrared effective model of the quantum dynamics of a boson gas.

AB - We construct a quantum kinetic theory of a weakly interacting critical boson gas using the expectation values of products of Heisenberg field operators in the grand canonical ensemble. Using a functional representation for the Wick theorem for time-ordered products, we construct a perturbation theory for the generating functional of these time-dependent Green’s functions at a finite temperature. We note some problems of the functional-integral representation and discuss unusual apparent divergences of the perturbation expansion. We propose a regularization of these divergences using attenuating propagators. Using a linear transformation to variables with well-defined scaling dimensions, we construct an infrared effective field theory. We show that the structure of the regularized model is restored by renormalization. We propose a multiplicatively renormalizable infrared effective model of the quantum dynamics of a boson gas.

KW - boson gas

KW - critical dynamics

KW - finite-temperature time Green’s function

KW - infrared effective model

KW - superfluid phase transition

UR - http://www.scopus.com/inward/record.url?scp=85073219398&partnerID=8YFLogxK

U2 - 10.1134/S0040577919090095

DO - 10.1134/S0040577919090095

M3 - Article

AN - SCOPUS:85073219398

VL - 200

SP - 1360

EP - 1373

JO - Theoretical and Mathematical Physics (Russian Federation)

JF - Theoretical and Mathematical Physics (Russian Federation)

SN - 0040-5779

IS - 3

ER -