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Bose-Einstein Condensation for Homogeneous Interacting Systems with a One-Particle Spectral Gap

J. Lauwers·A. Verbeure·V. A. Zagrebnov
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Abstract

We prove rigorously the occurrence of zero-mode Bose-Einstein condensation for a class of continuous homogeneous systems of boson particles with superstable interactions. This is the first example of a translation invariant continuous Bose-system, where the existence of the Bose-Einstein condensation is proved rigorously for the case of non-trivial two-body particle interactions, provided there is a large enough one-particle excitations spectral gap. The idea of proof consists of comparing the system with specially tuned soluble models.

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J. Lauwers, A. Verbeure, V. A. Zagrebnov. 2003-11-20. Bose-Einstein Condensation for Homogeneous Interacting Systems with a One-Particle Spectral Gap. https://arxiv.org/abs/math-ph/0303060

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