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Proof of Bose-Einstein Condensation for Interacting Gases with a One-Particle Spectral Gap

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

Using a specially tuned mean-field Bose gas as a reference system, we establish a positive lower bound on the condensate density for continuous Bose systems with superstable two-body interactions and a finite gap in the one-particle excitations spectrum, i.e. we prove for the first time standard homogeneous Bose-Einstein condensation for such interacting systems.

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J. Lauwers, A. Verbeure, V. A. Zagrebnov. 2003-03-10. Proof of Bose-Einstein Condensation for Interacting Gases with a One-Particle Spectral Gap. https://doi.org/10.1088/0305-4470%2F36%2F11%2F102

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