Speaker
Andre Walker-Loud
Description
Beta decays offer an opportunity for low-energy precision tests of the Standard Model, in particular, checking the unitarity of the first-row CKM matrix which connects the weak and QCD flavor bases. These tests require a combination of the experimental measurements, effective field theory and phenomenology, as well as lattice QCD for non-perturbative input. State of the art theory predictions require an understanding of radiative QED corrections at the 1e-4 level of precision. There is presently a ~3 sigma tension in first-row unitarity with exciting prospects to improve the experimental and theoretical inputs. I will describe some theoretical advances with am emphasis on lattice QCD contributions.