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arXiv · 1508.02416

U(1) axial symmetry and Dirac spectra in QCD at high temperature

Takuya Kanazawa·Naoki Yamamoto
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Abstract

We derive some exact results concerning the anomalous U(1)$_A$ symmetry in the chirally symmetric phase of QCD at high temperature. We discuss the importance of topology and finite-volume effects on the U(1)$_A$ symmetry violation characterized by the difference of chiral susceptibilities. In particular, we present a reliable method to measure the anomaly strength in lattice simulations with fixed topology. We also derive new spectral sum rules and a novel Banks-Casher-type relation. Through our spectral analysis we arrive at a simple alternative proof of the Aoki-Fukaya-Taniguchi "theorem" on the effective restoration of the U(1)$_A$ symmetry at high temperature.

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Takuya Kanazawa, Naoki Yamamoto. 2015-08-10. U(1) axial symmetry and Dirac spectra in QCD at high temperature. https://doi.org/10.1007/jhep01(2016)141

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