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Shift of BEC Temperature of Homogenous Weakly Interacting Bose Gas

Boris Kastening
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Abstract

We report on the computation of the shift of the Bose-Einstein condensation temperature for a homogenous weakly interacting Bose gas in leading order in the diluteness parameter a n^(1/3), where `a' is the scattering length and `n' is the particle density. The perturbative series, which is afflicted by infrared divergences, is resummed by means of variational perturbation theory. Using coefficients through seven loops, we arrive at Delta T_c/T_c = 1.27 +/- 0.11 a n^(1/3), which compares favorably with recent Monte-Carlo data.

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Boris Kastening. 2004-04-15. Shift of BEC Temperature of Homogenous Weakly Interacting Bose Gas. https://arxiv.org/abs/cond-mat/0404354

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