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arXiv · 2305.18959

Bose-Einstein condensation of interacting bosons: A two-step proof

Abstract

We prove two equilibrium properties of a system of interacting atoms in three or higher dimensional continuous space. (i) If the particles interact via pair potentials of a nonnegative Fourier transform, their self-organization into infinite permutation cycles is simultaneous with off-diagonal long-range order. If the cycle lengths tend to infinity not slower than the square of the linear extension of the system, there is also Bose-Einstein condensation. (ii) If the pair potential is also nonnegative, cycles composed of a nonzero fraction of the total number of particles do appear if the density exceeds a temperature-dependent threshold value. The two together constitute the proof that in such a system Bose-Einstein condensation takes place at high enough densities.

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Andras Suto. 2023-05-30. Bose-Einstein condensation of interacting bosons: A two-step proof. https://arxiv.org/abs/2305.18959

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