>>11759545honestly i think this is a very good idea. the ways we in experimental particle physics detect neutrinos are basically only sensitive to high-energy neutrinos. “cold” neutrinos are basically invisible. and just like the cosmic microwave background of photons is very low-energy compared to the gamma rays they started out as, with neutrinos, the cosmic background must have redshifted an incredible amount since the early universe. so that would make “primordial” neutrinos very “cold”, if we suppose they have a small but nonzero mass.
i think some good theorists have thought about this, and based on what we know the currently known neutrinos for not easily explain dark matter. that is why additional neutrinos or “sterile neutrinos” are favored as a possible explanation. but in any case, a better understanding of neutrinos would definitely help with our understanding of dark matter
