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Microscopic Evolution of a Weakly Interacting Homogeneous Bose Gas

D. G. Barci·E. S. Fraga·Rudnei O. Ramos
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Abstract

We provide a detailed description of the nonequilibrium time evolution of an interacting homogeneous Bose-Einstein condensate. We use a nonperturbative in-medium quantum field theory approach as a microscopic model for the Bose gas. The real-time dynamics of the condensate is encoded in a set of self-consistent equations which corresponds to an infinite sum of ladder Feynman diagrams. The crucial role played by the interaction between fluctuations for the instability generation is thoroughly described.

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D. G. Barci, E. S. Fraga, Rudnei O. Ramos. 2001-10-19. Microscopic Evolution of a Weakly Interacting Homogeneous Bose Gas. https://arxiv.org/abs/cond-mat/0104463

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