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arXiv · 0712.3170

Strong CP Problem with 10^{32} Standard Model Copies

Gia Dvali·Glennys R. Farrar
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Abstract

We show that a recently proposed solution to the Hierarchy Problem simultaneously solves the Strong CP Problem, without requiring an axion or any further new physics. Consistency of black hole physics implies a non-trivial relation between the number of particle species and particle masses, so that with ~10^{32} copies of the standard model, the TeV scale is naturally explained. At the same time, as shown here, this setup predicts a typical expected value of the strong-CP parameter in QCD of theta ~ 10^{-9}. This strongly motivates a more sensitive measurement of the neutron electric dipole moment.

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Gia Dvali, Glennys R. Farrar. 2007-12-19. Strong CP Problem with 10^{32} Standard Model Copies. https://doi.org/10.1103/physrevlett.101.011801

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