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Effect of CP-violation on the sphaleron rate

Bert-Jan Nauta
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Abstract

We calculate the effect of two CP-violating (dimension-eight) operators of the SU(2)-Higgs model on the motion along a particular path from the vacuum to the sphaleron. It turns out that CP-violation may introduce a difference between the sphaleron rate towards larger Chern-Simons number and the rate towards smaller Chern-Simons number. Such a difference induces a non-zero baryon-number without a first order phase transition.

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Bert-Jan Nauta. 2000-03-22. Effect of CP-violation on the sphaleron rate. https://doi.org/10.1016/s0370-2693(00)00284-7

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