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arXiv · 1305.1627

Spontaneous breaking of the flavor symmetry avoids the strong CP problem

Chee Sheng Fong·Enrico Nardi
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Abstract

A promising approach to the Standard Model flavor puzzle is based on the idea that the $SU(3)^3$ quark-flavor symmetry is spontaneously broken by vacuum expectation values of `Yukawa fields' which minimize the symmetry invariant scalar potential at configurations corresponding to the observed quark masses and mixing angles. We show that this approach provides a simple and elegant explanation for CP conservation in strong interactions.

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Chee Sheng Fong, Enrico Nardi. 2013-05-07. Spontaneous breaking of the flavor symmetry avoids the strong CP problem. https://doi.org/10.1103/physrevlett.111.061601

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