Small-Scale Crisis in Cosmology – Sterile Neutrinos to the Rescue?
Peer reviewed, Journal article
MetadataVis full innførsel
The ΛCDM standard model of cosmology is in excellent agreement with data on large scales but has difficulty explaining all observations on small scales. I discuss a simple particle physics model involving a new MeV-scale gauge boson that mediates dark matter self-interactions and dark matter interactions with a new light fermion. This allows to solve all small-scale problems of ΛCDM cosmology. It would be very attractive to identify the new light particle with a sterile neutrino, but it appears that this option is disfavored.