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Chiral symmetry and spectrum of Euclidean Dirac operator

Sebastien Descotes
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Abstract

After recalling some connections between the Spontaneous Breakdown of Chiral Symmetry (SBChS) and the spectrum of the Dirac operator for Euclidean QCD on a torus, we use this tool to reconsider two related issues : the Zweig rule violation in the scalar channel and the dependence of SBChS order parameters on the number N_f of massless flavours. The latter would result into a great variety of SBChS patterns in the (N_f,N_c) plane, which could be studied through so-called Leutwyler-Smilga sum rules in association with lattice computations of the Dirac spectrum.

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Sebastien Descotes. 1999-11-09. Chiral symmetry and spectrum of Euclidean Dirac operator. https://arxiv.org/abs/hep-ph/9911285

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