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arXiv · 2404.19197

Does the Electron EDM Preclude Electroweak Baryogenesis ?

Yuan-Zhen Li·Michael J. Ramsey-Musolf·Jiang-Hao Yu
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Abstract

Electroweak baryogenesis (EWBG) constitutes a theoretically compelling and experimentally testable mechanism for explaining the origin of the baryon asymmetry of the universe (BAU). New results for the electric dipole moment (EDM) of the electron place significant constraints on the beyond Standard Model CP-violation needed for successful EWBG. Using a specific model illustration, we show how new developments in EWBG quantum transport theory that include CP-violating sources first order in gradients imply more relaxed EDM constraints -- and thereby greater EWBG viability -- than implied by previous approximation formulations. We also illustrate how these developments enable a more realistic treatment of CP-conserving interactions that can also have a decisive impact on the predicted BAU.

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Yuan-Zhen Li, Michael J. Ramsey-Musolf, Jiang-Hao Yu. 2024-04-30. Does the Electron EDM Preclude Electroweak Baryogenesis ?. https://doi.org/10.1016/j.physletb.2026.140503

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