Two Sides of the Same Coin: Sterile Neutrinos and Dark Radiation, Status and Perspectives
Two Sides of the Same Coin: Sterile Neutrinos and Dark Radiation, Status and Perspectives
The presence of light sterile neutrinos is one of the unanswered questions of particle physics. The cosmological counterpart is represented by dark radiation, i.e., any form of radiation present in the early Universe besides photons and standard (active) neutrinos. This short review provides a comprehensive overview of the two problems …