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arXiv · 2007.06448

On the effect of repulsive interactions on Bose-Einstein condensation in the Luttinger-Sy model

Joachim Kerner·Maximilian Pechmann
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Abstract

In this paper we investigate the effect of repulsive pair interactions on Bose-Einstein condensation in a well-established random one-dimensional system known as the Luttinger-Sy model at positive temperature. We study separately hard core interactions as well as a class of more general repulsive interactions, also allowing for a scaling of certain interaction parameters in the thermodynamic limit. As a main result, we prove in both cases that for sufficiently strong interactions all eigenstates of the non-interacting one-particle Luttinger-Sy Hamiltonian as well as any sufficiently localized one-particle state are almost surely not macroscopically occupied.

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Joachim Kerner, Maximilian Pechmann. 2020-07-13. On the effect of repulsive interactions on Bose-Einstein condensation in the Luttinger-Sy model. https://doi.org/10.1090/proc/15424

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