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arXiv · 1110.2715

Flavor symmetry breaking in mixed-action QCD

Oliver Baer·Maarten Golterman·Yigal Shamir
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Abstract

We study the phase structure of mixed-action QCD with two Wilson sea quarks and two chiral valence quarks, starting from the chiral lagrangian. A priori, the effective theory allows for a rich phase structure, including a phase with a condensate made of sea and valence quarks. Because this would lead to mass eigenstates that are admixtures of sea and valence fields, pure-sea correlation functions would depend on valence quark masses, in contradiction with the actual setup of mixed-action simulations. Using properties of the chiral Dirac operator, we prove that such a phase does not occur, and that this leads to bounds on low-energy constants.

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Oliver Baer, Maarten Golterman, Yigal Shamir. 2011-10-12. Flavor symmetry breaking in mixed-action QCD. https://arxiv.org/abs/1110.2715

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