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A Physical Explanation for Tilde System in Thermo Field Dynamics

Dong Mi·He-Shan Song·Ying An
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Abstract

For a two-body quantum system, any pure state can be represented by a biorthogonal expression by means of Schmidt decomposition. Using this in the composite system which include a thermodynamic system and its surroundings, it is found that the tilde system in thermo field dynamics is just the surroundings of the real system.

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Dong Mi, He-Shan Song, Ying An. 2001-02-25. A Physical Explanation for Tilde System in Thermo Field Dynamics. https://doi.org/10.1142/s0217732301003607

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