Integral representations of thermodynamic 1PI Green functions in the world-line formalism

Haru-Tada Sato

doi:10.1063/1.533100

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arXiv · hep-th/9809053

Integral representations of thermodynamic 1PI Green functions in the world-line formalism

Haru-Tada Sato

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Abstract

The issue discussed is a thermodynamic version of the Bern-Kosower master amplitude formula, which contains all necessary one-loop Feynman diagrams. It is demonstrated how the master amplitude at finite values of temperature and chemical potential can be formulated within the framework of the world-line formalism. In particular we present an elegant method how to introduce a chemical potential for a loop in the master formula. Various useful integral formulae for the master amplitude are then obtained. The non-analytic property of the master formula is also derived in the zero temperature limit with the value of chemical potential kept finite.

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Haru-Tada Sato. 1999-02-03. Integral representations of thermodynamic 1PI Green functions in the world-line formalism. https://doi.org/10.1063/1.533100

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