arXiv:1411.7330 · Journal of Mathematical Physics

Instability of Bose-Einstein condensation into the one-particle ground state on quantum graphs under repulsive perturbations

Jens Bolte, Joachim Kerner

Published Apr 1, 2016• 8 citations

Abstract

In this paper we investigate Bose-Einstein condensation into the one-particle ground state in interacting quantum many-particle systems on graphs. We extend previous results obtained for particles on an interval and show that even arbitrarily small repulsive two-particle interactions destroy the condensate in the one-particle ground state present in the non-interacting Bose gas. Our results also cover singular two-particle interactions, such as the well-known Lieb-Liniger model, in the thermodynamic limit.

DOI: 10.1063/1.4946044

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