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arXiv · 0906.3434

Lepton asymmetry and the cosmic QCD transition

Dominik J Schwarz·Maik Stuke
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Abstract

We study the influence of lepton asymmetry on the evolution of the early Universe. The lepton asymmetry $l$ is poorly constrained by observations and might be orders of magnitude larger than the baryon asymmetry $b$, $|l|/b \leq 2\times 10^8$. We find that lepton asymmetries that are large compared to the tiny baryon asymmetry, can influence the dynamics of the QCD phase transition significantly. The cosmic trajectory in the $\mu_B-T$ phase diagram of strongly interacting matter becomes a function of lepton (flavour) asymmetry. Large lepton asymmetry could lead to a cosmic QCD phase transition of first order.

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Dominik J Schwarz, Maik Stuke. 2009-06-18. Lepton asymmetry and the cosmic QCD transition. https://doi.org/10.1088/1475-7516/2009/11/025 10.1088/1475-7516/2010/10/e01

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