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arXiv · 1210.2438

Phase quenching in finite-density QCD: models, holography, and lattice

Masanori Hanada·Yoshinori Matsuo·Naoki Yamamoto
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Abstract

Finite-density QCD is difficult to study numerically because of the sign problem. We prove that, in a certain region of the phase diagram, the phase quenched approximation is exact to O(Nf/Nc). It is true for any physical observables. We also consider the implications for the lattice simulations and find a quantitative evidence for the validity of the phase quenching from existing lattice QCD results at Nc=3. Our results show that the phase-quench approximation is rather good already at Nc=3, and the 1/Nc correction can be incorporated by the phase reweighting method without suffering from the overlap problem. We also show the same equivalence in effective models and holographic models.

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Masanori Hanada, Yoshinori Matsuo, Naoki Yamamoto. 2012-10-08. Phase quenching in finite-density QCD: models, holography, and lattice. https://arxiv.org/abs/1210.2438

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