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arXiv · 2102.07224

Gap in the Dirac spectrum and quark propagator symmetries in lattice QCD

Marco Catillo
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Abstract

Recent studies on lattice QCD have shown the emergence of large symmetries at high temperature. This includes not only the restoration $SU(n_F)_L \times SU(n_F)_R$, but also the effective emergence of an unexpected symmetry group, namely $SU(2)_{CS}$, which contains $U(1)_A$ as subgroup. At the same time, at high $T$, a gap in Dirac spectrum appears. As it is argued in several works of \textit{L. Glozman et al.}, there should be a connection between a gap in the Dirac spectrum and the presence of $SU(2)_{CS}$.In this paper, we analyze whether the quark propagator can be invariant under $SU(n_F)_L \times SU(n_F)_R$ and $SU(2)_{CS}$ transformations, in case of a gap in the Dirac spectrum, and consequently the invariance of hadron correlators, giving the condition for a quark propagator to be invariant under $SU(2)_{CS}$.

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Marco Catillo. 2021-02-14. Gap in the Dirac spectrum and quark propagator symmetries in lattice QCD. https://arxiv.org/abs/2102.07224

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