Early Universe production of $W$ bosons in neutrino decays

TL;DR

This paper calculates the production rates of $W$ bosons from neutrino decays in the early Universe's de Sitter spacetime using perturbative quantum field theory methods.

Contribution

It provides a detailed perturbative calculation of $W$ boson production rates in early Universe conditions, including regularization and limiting case analysis.

Findings

Derived transition rates for $W$ boson production in de Sitter space.

Analyzed the density number of $W$ bosons with respect to momenta and renormalization mass.

Presented a framework for understanding electroweak particle production in early cosmological epochs.

Abstract

In this paper we study, via perturbative methods, the rates of production of $W$ bosons emitted in neutrino decays during the early stages of the Universe. We compute the transition amplitude corresponding to the first order of de Sitter electroweak perturbation theory and study its various limiting cases. The transition rates are derived using minimal subtraction and dimensional regularization. In the end we attempt to obtain the density number of $W$ bosons produced in perturbative transitions in de Sitter spacetime, using the rates obtained in this paper and in previous ones, and analyze the density number with respect to the particle momenta and renormalisation mass $\mu$.