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arXiv · 0810.4368

Naturalness of CP Violation in the Standard Model

Gary W. Gibbons·Steffen Gielen·C. N. Pope·Neil Turok
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Abstract

We construct a natural measure on the space of CKM matrices in the standard model, assuming the fermion mass matrices are randomly selected from a distribution which fits the observed quark mass hierarchy. This measure allows us to assess the likelihood of Jarlskog's CP violation parameter J taking its observed value J $\approx$ 3 x 10^{-5}. While well below the mathematically allowed maximum, we find that this value is in fact typical, once the observed quark masses are assumed.

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Gary W. Gibbons, Steffen Gielen, C. N. Pope, Neil Turok. 2009-01-21. Naturalness of CP Violation in the Standard Model. https://doi.org/10.1103/physrevlett.102.121802

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