Generalizations of the thermal Bogoliubov transformation

P. Elmfors; H. Umezawa

doi:10.1016/0378-4371(94)90480-4

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arXiv · hep-th/9304089

Generalizations of the thermal Bogoliubov transformation

P. Elmfors·H. Umezawa

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Abstract

The thermal Bogoliubov transformation in thermo field dynamics is generalized in two respects. First, a generalization of the $α$--degree of freedom to tilde non--conserving representations is considered. Secondly, the usual $2\times2$ Bogoliubov matrix is extended to a $4\times4$ matrix including mixing of modes with non--trivial multiparticle correlations. The analysis is carried out for both bosons and fermions.

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P. Elmfors, H. Umezawa. 1993-04-21. Generalizations of the thermal Bogoliubov transformation. https://doi.org/10.1016/0378-4371(94)90480-4

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