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Asymptotic behaviours of the heat kernel in covariant perturbation theory

A. O. Barvinsky·Yu. V. Gusev·G. A. Vilkovisky·V. V. Zhytnikov
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Abstract

The trace of the heat kernel is expanded in a basis of nonlocal curvature invariants of $N$th order. The coefficients of this expansion (the nonlocal form factors) are calculated to third order in the curvature inclusive. The early-time and late-time asymptotic behaviours of the trace of the heat kernel are presented with this accuracy. The late-time behaviour gives the criterion of analyticity of the effective action in quantum field theory. The latter point is exemplified by deriving the effective action in two dimensions.

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A. O. Barvinsky, Yu. V. Gusev, G. A. Vilkovisky, V. V. Zhytnikov. 1994-04-29. Asymptotic behaviours of the heat kernel in covariant perturbation theory. https://doi.org/10.1063/1.530428

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