Session G01: Physical Review: Neutrino Mass

Theory overview: Why is the neutrino mass important

Neutrinos are the most mysterious and interesting particles of matter known. Their study has provided us with essential information for the construction of the standard model and, subsequently, the only experimental evidence we have that it needs to be extended. This was obtained thanks to neutrino oscillation experiments, that proved that neutrinos have mass.

There are exciting possibilities to deepen further the  study of their mass, first of all by new and more sensitive neutrino oscillation experiments, by direct measurements, and finally, by observing for the first time the transformation called neutrinoless double beta decay - a hypothetical nuclear transition in which two electrons are created.

In this review talk, we will discuss what is the significance of neutrino masses, what are the current theoretical expectations of their value, what are the most promising directions of development for the theory and why it is important to proceed in these studies.   

Current and future laboratory constraints on the neutrino mass

The turn of the 21st century witnessed a sudden shift in our fundamental understanding of particle physics. While the minimal Standard Model predicts that neutrino masses are exactly zero, the discovery of neutrino oscillations proved the Standard Model wrong. Neutrino oscillation measurements, however, shed light neither on the scale of neutrino masses, nor on the mechanism by which those are generated. The neutrino mass scale is most directly accessed by studying the energy spectrum generated by beta decay or electron capture — a technique dating back to Enrico Fermi's formulation of radioactive decay. In this talk, I review the methods and techniques – both past and present – aimed at measuring neutrino masses kinematically. I will focus on recent experimental developments that have emerged in the past decade, and provide an outlook of what future experiments might be able to achieve.   

Neutrino mass scale from cosmological constraints

In this talk, we shall present the latest and tightest cosmological constraints on the neutrino mass scale and the prospects from future surveys. Special attention will be devoted to the interplay between cosmological and laboratory neutrino mass searches, along with the role of neutrinos in solving the present cosmological tensions.