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arXiv · 2510.23351

Pseudodifferential calculus in Schwinger--DeWitt formalism: UV and IR parts

A. O. Barvinsky·A. E. Kalugin·W. Wachowski
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Abstract

We consider expansions for the kernels of operator functions of second-order minimal operators on a curved background. We show that the terms of these expansions originate in the ultraviolet or infrared regions. We propose a systematic approach to obtaining ultraviolet terms using term-by-term integration of the DeWitt expansion of the heat kernel. We discuss two methods for regularizing infrared divergences arising at intermediate computational steps -- using analytic continuation and introducing a mass term -- and the relationship between them.

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A. O. Barvinsky, A. E. Kalugin, W. Wachowski. 2025-10-27. Pseudodifferential calculus in Schwinger--DeWitt formalism: UV and IR parts. https://doi.org/10.1016/j.physletb.2026.140291

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