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Asymmetric Chern-Simons number diffusion from CP-violation

Bert-Jan Nauta·Alejandro Arrizabalaga
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Abstract

We study Chern-Simons number diffusion in a SU(2)-Higgs model with CP-odd dimension-eight operators. We find that the thermal average of the magnitude of the velocity of the Chern-Simons number depends on the direction of the velocity. This implies that the distribution function of the Chern-Simons number will develop an asymmetry. It is argued that this asymmetry manifests itself through a linear growth of the expectation value of the third power of the Chern-Simons number. This linear behavior of the third power of a coordinate of a periodic direction is verified by a numerical solution of a one-dimensional Langevin equation. Further, we make some general remarks on thermal averages and on the possibility of the generation of the baryon asymmetry in a non-equilibrium situation due to asymmetric diffusion of the Chern-Simons number.

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Bert-Jan Nauta, Alejandro Arrizabalaga. 2002-02-12. Asymmetric Chern-Simons number diffusion from CP-violation. https://doi.org/10.1016/s0550-3213(02)00355-3

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