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Thermal Operator Representation of Finite Temperature Graphs

Fernando T. Brandt·Ashok Das·Olivier Espinosa·Josif Frenkel·Silvana Perez
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Abstract

Using the mixed space representation (t,p) in the context of scalar field theories, we prove in a simple manner that the Feynman graphs at finite temperature are related to the corresponding zero temperature diagrams through a simple thermal operator, both in the imaginary time as well as in the real time formalisms. This result is generalized to the case when there is a nontrivial chemical potential present. Several interesting properties of the thermal operator are also discussed.

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Fernando T. Brandt, Ashok Das, Olivier Espinosa, Josif Frenkel, Silvana Perez. 2005-08-09. Thermal Operator Representation of Finite Temperature Graphs. https://doi.org/10.1103/physrevd.72.085006

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