In physical cosmology, the lepton epoch was the period in the evolution of the early universe in which the leptons dominated the mass of the Universe. It started roughly 1 second after the Big Bang, after the majority of hadrons and anti-hadrons annihilated each other at the end of the hadron epoch. During the lepton epoch the temperature of the Universe was still high enough to create neutrino and electron-positron pairs. Approximately 10 seconds after the Big Bang the temperature of the universe had fallen to the point where electron-positron pairs were gradually annihilated. A small residue of electrons needed to charge-neutralize the Universe remained along with free streaming neutrinos: an important aspect of this epoch is the neutrino decoupling. The Big Bang nucleosynthesis epoch follows overlapping with the photon epoch.
- Fromerth, M.J.; Kuznetsova, I.; Labun, L.; Letessier, J.; Rafelski, J. (2012). "From Quark-Gluon Universe to Neutrino Decoupling: 200 < T < 2MeV". Acta Physica Polonica B. 43 (12): 2261. doi:10.5506/APhysPolB.43.2261. ISSN 0587-4254.
- "Thermal history of the Universe and early growth of density fluctuations" (PDF). Guinevere Kauffmann. Max Planck Institute for Astrophysics. Retrieved 2016-01-06.
- Birrell, Jeremiah; Yang, Cheng Tao; Rafelski, Johann (2015). "Relic neutrino freeze-out: Dependence on natural constants". Nuclear Physics B. 890: 481–517. doi:10.1016/j.nuclphysb.2014.11.020.
- "First few minutes". Eric Chaisson. Havard Smithsonian Center for Astrophysics. Retrieved 2016-01-06.
- "Timeline of the Big Bang". The physics of the Universe. Retrieved 2016-01-06.
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