Seminarium "Teoria cząstek elementarnych i kosmologia"

Neutrinos offer a window into beyond Standard Model (BSM) physics, and recent data prompt a re-evaluation of their role in the early universe. Neutrino portals facilitate thermal Dark Matter (DM) production, representing one of the few remaining benchmarks in the freeze-out paradigm, yet a difficult one to probe. In this talk, we first summarize constraints on such scenarios and discuss how recent and near-future cosmological data may soon illuminate these dark sectors. The latter part emphasizes the impact of resonant DM-neutrino scattering on perturbation evolution. We illustrate that incorporating these precision effects, typically associated with collider physics, significantly alters cosmological data analysis, with implications extending beyond the specific models discussed.