Abstract: According to the SM, neutrinos are massless particles. However, in recent decades we have discovered and experimentally tested --with a precision that leaves no room for doubt-- that neutrinos do have mass. These are the first direct experimental proof that the SM, or fundamental particle physics as we know it, is incomplete. Since neutrinos are the first particles that have experimentally warned us that the SM is incomplete, why not use them to find out exactly what is missing? In this thesis defense, I will explain three scenarios --different and complementary-- in which we can use neutrinos to discover what physics is beyond the SM. These are: neutrino oscillations (sterile neutrino searches in the wave packet formalism), ultra-high-energy neutrino astrophysics (a BSM origin of the ANITA-IV events), and neutrino cosmology (the mass measurement; and nu-ULDM interactions). These four projects have one thing in common: they aim to better understand the potential of experiments for neutrino phenomenology and to rethink the hypotheses conventionally assumed behind their conclusions.

Tribunal:

President: Dr. Miguel Escudero Abenza

Secretary: Dr. María Concepción González García

Vocal: Dr. Jacobo López Pavón

Suplents:

Dr. Javier Virto Iñigo

Dr. Sergio Palomares Ruiz

Director: Dr. Jordi Salvadó Serra

Tutor: Dr. Joan Soto Riera