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arXiv · 1208.0761

Elucidating the Vacuum Structure of the Aoki Phase

Vicente Azcoiti·Giuseppe Di Carlo·Eduardo Follana·Alejandro Vaquero
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Abstract

In this paper, we discuss the vacuum structure of QCD with two flavors of Wilson fermions, inside the Aoki phase. We provide numerical evidence, coming from HMC simulations in $4^4$, $6^4$ and $8^4$ lattices, supporting a vacuum structure for this model at strong coupling more complex than the one assumed in the standard wisdom, with new vacua where the expectation value of $i\barψγ_5ψ$ can take non-zero values, and which can not be connected with the Aoki vacua by parity-flavour symmetry transformations.

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Vicente Azcoiti, Giuseppe Di Carlo, Eduardo Follana, Alejandro Vaquero. 2013-01-21. Elucidating the Vacuum Structure of the Aoki Phase. https://doi.org/10.1016/j.nuclphysb.2013.01.008

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