Applicability of the Wigner functional approach to evolution of quantum fields

A. V. Leonidov, A. A. Radovskaya

Published Oct 28, 2016• 4 citations

Abstract

\nEvolution of highly excited quantum field is considered in the framework of Keldysh formalism . It is demonstrated that leading order (LO) term of semiclassical approximation appears as well-known Classical Statistical Approximation (CSA). In simple case of spatially homogeneous scalar field analytical expressions for leading and next-to-leading (NLO) order are presented. It is shown that the range of applicability of CSA strongly depends on the properties of the initial state of the system.\n

DOI: 10.1051/epjconf/201612505013/pdf

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