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The Unique Derivative Expansion for Thermal Effective Actions

T. S. Evans
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Abstract

I show that there is a unique and well behaved derivative expansion of an effective action at finite temperature. The result is true for all formalisms including the popular Closed Time Path and Imaginary Time methods.

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T. S. Evans. 1998-09-16. The Unique Derivative Expansion for Thermal Effective Actions. https://arxiv.org/abs/hep-ph/9808383

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