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arXiv · hep-ph/0310342

Baryon asymmetry from electroweak tachyonic preheating

Abstract

We consider a scenario in which the baryon asymmetry was created in the early universe during a cold electroweak transition. The spinodal instability of the Higgs field caused by a rapid change of sign of its effective mass-squared parameter induces tachyonic preheating. We study the development of Chern-Simons number in this transition by numerical lattice simulations of the SU(2)-Higgs model with an added effective CP-violating term. A net asymmetry is produced, and we study its dependence on the size of CP violation and the ratio of Higgs to W mass.

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Anders Tranberg, Jan Smit. 2003-10-30. Baryon asymmetry from electroweak tachyonic preheating. https://doi.org/10.1088/1126-6708%2F2003%2F11%2F016

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