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arXiv · hep-ph/9203206

Solutions to the strong CP problem in a world with gravity

R. Holman·S. D. H. Hsu·T. Kephart·E. Kolb·R. Watkins·L. Widrow
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Abstract

We examine the sensitivity of several solutions of the strong-CP problem to violations of global symmetries by Planck scale physics. We find that the Peccei-Quinn solution is extremely sensitive to U(1)_PQ violating operators of dimension less than 10. We construct models in which the PQ symmetry is protected by gauge symmetries to the requisite level.

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R. Holman, S. D. H. Hsu, T. Kephart, E. Kolb, R. Watkins, L. Widrow. 1992-03-09. Solutions to the strong CP problem in a world with gravity. https://doi.org/10.1016/0370-2693(92)90491-l

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