Journal of Mathematical Physics

Gentle perturbations of the free Bose gas. The critical regime

Roman Gielerak, Robert Olkiewicz

Published Mar 1, 1996• 2 citations

Abstract

The modular structure of the free Bose gas in the critical regime of couplings is completely described by certain Gaussian Markovian (on a circle) nonergodic thermal process. Gentle perturbations of the arising Gaussian stochastic structure are controlled rigorously and the arising non-quasi-free W* KMS structure is shown to be nonergodic in certain range of couplings. The preserved nonergodicity seems to be connected to the presence of the Bose–Einstein condensate in the constructed models of interacting bosons.

DOI: 10.1063/1.531462

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