It was the best of times, it was the worst of times. Just as the classic English novel lends its title well to the spirit of understanding symmetries in the standard model (SM), the opening words also concisely sum up the status of beyond standard model (BSM) physics searches through tests of the fundamental symmetric matrices over the past few decades. Despite the identical mathematical formalism that generates these matrices in the SM, empirically the level of observed mixing within these two are dramatically different. Understanding the underlying physics that generates these differences may perhaps be one of our best portals into BSM physics and the dark sector. In this seminar, I will discuss in detail the precision nuclear decay measurements and theoretical corrections that go in to precision tests of the top-row unitarity condition of the CKM matrix. I will also discuss precision limits on the neutrino mass(es) obtained from weak decay experiments, and in both cases will focus on how we can use modern experimental techniques to push tests of these fundamental symmetries beyond the current state-of-the-art.
Host: Thomas Penny