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arXiv · 1411.7330

Instability of Bose-Einstein condensation on quantum graphs under repulsive perturbations

Jens Bolte·Joachim Kerner
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Abstract

In this Note we investigate Bose-Einstein condensation 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 a condensate in the non-interacting Bose gas. Our results also cover singular two-particle interactions, such as the well-known Lieb-Lininger model, in the thermodynamic limit.

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Jens Bolte, Joachim Kerner. 2014-11-26. Instability of Bose-Einstein condensation on quantum graphs under repulsive perturbations. https://doi.org/10.1063/1.4946044

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