Boriero, Daniel FranciscoSchwarz, Dominik J.Velten, Hermano Endlich Schneider2023-01-182023-01-182019BORIERO, D. F.; SCHWAZ, D. J.; VELTEN, H. E. S. Flavour composition and entropy increase of cosmological neutrinos after decoherence. Universe, v. 5, n. 10, artigo 203, 2019. Disponível em: <https://www.mdpi.com/2218-1997/5/10/203>. Acesso em: 06 jul. 2022.2218-1997http://www.repositorio.ufop.br/jspui/handle/123456789/16002We propose that gravitational interactions of cosmic neutrinos with the statistically homogeneous and isotropic fluctuations of space-time lead to decoherence. This working hypothesis, which we describe by means of a Lindblad operator, is applied to the system of two- and three-flavour neutrinos undergoing vacuum oscillations and the consequences are investigated. As a result of this decoherence we find that the neutrino entropy would increase as a function of initial spectral distortions, mixing angles and charge-parity (CP)-violation phase. Subsequently we discuss the chances to discover such an increase observationally (in principle). We also present the expected flavour composition of the cosmic neutrino background after decoherence is completed. The physics of two- or three-flavour oscillation of cosmological neutrinos resembles in many aspects two- or three-level systems in atomic clocks, which were recently proposed by Weinberg for the study of decoherence phenomena.en-USabertoCosmologyNeutrino oscillationsCosmic neutrino backgroundFlavour composition and entropy increase of cosmological neutrinos after decoherence.Artigo publicado em periodicoThis article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). Fonte: o PDF do artigo.https://doi.org/10.3390/universe5100203