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arXiv · 2203.09713

Lepton Asymmetric Universe

Masahiro Kawasaki·Kai Murai
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Abstract

The recent observation of $^4$He implies that our universe has a large lepton asymmetry. We consider the Affleck-Dine (AD) mechanism for lepton number generation. In the AD mechanism, non-topological solitons called L-balls are produced, and the generated lepton number is confined in them. The L-balls protect the generated lepton number from being converted to baryon number through the sphaleron processes. We study the formation and evolution of the L-balls and find that the universe with large lepton asymmetry suggested by the recent $^4$He measurement can be realized.

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Masahiro Kawasaki, Kai Murai. 2022-03-18. Lepton Asymmetric Universe. https://doi.org/10.1088/1475-7516%2F2022%2F08%2F041

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