# Low-energy limit of the O(4) quark-meson model

## TL;DR

This paper investigates how quantum fluctuations generate low-energy interactions in the O(4)-symmetric quark-meson model by using the functional renormalization group to derive an effective pion action, aiding future QCD studies.

## Contribution

It introduces a method to derive the low-energy limit of the quark-meson model including higher-derivative interactions using functional renormalization group techniques.

## Key findings

- Computed the RG flow including higher-derivative terms.
- Transformed the effective action into a nonlinear pion model.
- Provides groundwork for deriving low-energy couplings from QCD fluctuations.

## Abstract

We study the generation of low-energy couplings induced by quantum fluctuations within the O(4)-symmetric quark-meson model. To this end, we compute the functional renormalization group flow of the linearly realized quark-meson model including higher-derivative interactions and subsequently transform the resulting effective action into a nonlinear effective pion action. The latter is referred to as the low-energy limit of the O(4) quark-meson model. The present study may be considered as a preparatory work for the dynamical generation of low-energy couplings from functional QCD fluctuations in order to determine meaningful renormalization scales for purely pionic models.

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Source: https://tomesphere.com/paper/1902.04804