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arXiv · hep-ph/0202171

Higher-Dimensional QCD without the Strong CP Problem

K. -I. Izawa·T. Watari·T. Yanagida
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Abstract

QCD in a five-dimensional sliced bulk with chiral extra-quarks on the boundaries is generically free from the strong CP problem. Accidental axial symmetry is naturally present except for suppressed breaking interactions, which plays a role of the Peccei-Quinn symmetry to make the strong CP phase sufficiently small.

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K. -I. Izawa, T. Watari, T. Yanagida. 2002-03-28. Higher-Dimensional QCD without the Strong CP Problem. https://doi.org/10.1016/s0370-2693(02)01663-5

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