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Understanding chiral symmetry breaking with the overlap action

Thomas DeGrand
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Abstract

A chiral fermion action allows one to do very clean studies of chiral symmetry breaking in QCD. I will briefly describe how to compute with the overlap action (relatively) cheaply, and then turn to physics: Low modes of the Dirac operator show a ``lumped'' chiral density which peaks at the locations of instantons and anti-instantons. These modes dominate correlation functions at small quark mass in many channels. The picture qualitatively (and in some cases quantitatively) resembles an instanton liquid model.

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Thomas DeGrand. 2001-10-02. Understanding chiral symmetry breaking with the overlap action. https://arxiv.org/abs/hep-lat/0110005

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