Microscopic theory of a phase transition in a critical region: Bose-Einstein condensation in an interacting gas

Vitaly V. Kocharovsky; Vladimir V. Kocharovsky

doi:10.1016/j.physleta.2014.10.052

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arXiv · 1510.07333

Microscopic theory of a phase transition in a critical region: Bose-Einstein condensation in an interacting gas

Vitaly V. Kocharovsky·Vladimir V. Kocharovsky

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Abstract

We present a microscopic theory of the second order phase transition in an interacting Bose gas that allows one to describe formation of an ordered condensate phase from a disordered phase across an entire critical region continuously. We derive the exact fundamental equations for a condensate wave function and the Green functions, which are valid both inside and outside the critical region. They are reduced to the usual Gross-Pitaevskii and Beliaev-Popov equations in a low-temperature limit outside the critical region. The theory is readily extendable to other phase transitions, in particular, in the physics of condensed matter and quantum fields.

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Vitaly V. Kocharovsky, Vladimir V. Kocharovsky. 2015-10-26. Microscopic theory of a phase transition in a critical region: Bose-Einstein condensation in an interacting gas. https://doi.org/10.1016/j.physleta.2014.10.052

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