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arXiv · hep-th/0602140

Convexity of the effective action from functional flows

Daniel F. Litim·Jan M. Pawlowski·Lautaro Vergara
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Abstract

We show that convexity of the effective action follows from its functional flow equation. Our analysis is based on a new, spectral representation. The results are relevant for the study of physical instabilities. We also derive constraints for convexity-preserving regulators within general truncation schemes including proper-time flows, and bounds for infrared anomalous dimensions of propagators.

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Daniel F. Litim, Jan M. Pawlowski, Lautaro Vergara. 2006-02-14. Convexity of the effective action from functional flows. https://arxiv.org/abs/hep-th/0602140

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