Derivation of non-Markoffian transport equations for trapped cold atoms in nonequilibrium thermal field theory

Y. Nakamura; T. Sunaga; M. Mine; M. Okumura; Y. Yamanaka

doi:10.1016/j.aop/2009.09.014

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arXiv · 0907.5061

Derivation of non-Markoffian transport equations for trapped cold atoms in nonequilibrium thermal field theory

Y. Nakamura·T. Sunaga·M. Mine·M. Okumura·Y. Yamanaka

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Abstract

The non-Markoffian transport equations for the systems of cold Bose atoms confined by a external potential both without and with a Bose-Einstein condensate are derived in the framework of nonequilibrium thermal filed theory (Thermo Field Dynamics). Our key elements are an explicit particle representation and a self-consistent renormalization condition which are essential in thermal field theory. The non-Markoffian transport equation for the non-condensed system, derived at the two-loop level, is reduced in the Markoffian limit to the ordinary quantum Boltzmann equation derived in the other methods. For the condensed system, we derive a new transport equation with an additional collision term which becomes important in the Landau instability.

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Y. Nakamura, T. Sunaga, M. Mine, M. Okumura, Y. Yamanaka. 2009-07-29. Derivation of non-Markoffian transport equations for trapped cold atoms in nonequilibrium thermal field theory. https://doi.org/10.1016/j.aop/2009.09.014

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