In particle physics, the Standard Model (SM) is nowadays facing a watershed: it both shows its power in predicting the properties of the known fundamental particles and their interactions, while at the same time various evidences hint at a more comprehensive yet nowadays lacking underlying theory of Nature. Various phenomenological aspects are currently not captured by the SM, including the evidence for the existence of dark matter (DM), the asymmetry between matter and antimatter in the Universe, the evidence that neutrinos have masses, and the lack of CP violation by the strong forces. Answering these questions would significantly advance our knowledge of fundamental physics. The proposed programme aims to shed light on all of these keys aspects, exploring their intimate connections, addressing the feasibility and consequences of the proposed solutions. In more depth, this research programme will: I) Investigate numerically the evolution in the Early Universe of an extremely well-motivated DM particle candidate, the axion, including some of its phenomenological aspects; II) Discuss the generation of the matterantimatter asymmetry in the Early Universe in models with right-handed neutrinos, in leptogenesis scenarios; III) Assess the most recent, comprehensive models of neutrino mass generation in light of the state-of-the-art cosmological and astrophysical data. Dissemination will be implemented through the publication of articles in high-impact journals, contributions to international conferences, and outreach activities including participation in open-door initiatives at the host institute. The success of this proposal will be of extreme value in assessing the physics of the neutrino and of the axion in light of current data and future searches, as well as providing numerical tools for leptogenesis models. In addition, it will reinforce the leading position of INFN in the international scientific community devoted to fundamental physics.

Luca Visinelli – Laboratori Nazionali di Frascati