Joint Theory Seminar
Speaker: Peter Stoffer (UCSD)
Email: pstoffer@ucsd.edu
Title: EFT below the electroweak scale and constraints from electric dipole moments
Host: Xiaochuan Lu
Room: 432
Abstract: Under the assumption that physics beyond the standard model consists of heavy particles well above the electroweak scale, its effects at lower energies can be described by an effective field theory, either SMEFT or HEFT above the electroweak scale. Below the electroweak scale, either theory should be mapped to a low-energy EFT (LEFT), where the heavy standard-model particles are integrated out. This is essentially the well-known Fermi theory of weak interactions. I will present the complete LEFT operator basis up to dimension six (which, surprisingly, so far was missing in the literature) as well as the calculation of the full one-loop RGEs.
At low energies, strong constraints on some LEFT Wilson coefficients come from electric dipole moments. In order to exploit the full power of neutron EDM measurements, the uncertainties of hadronic matrix elements should be reduced, e.g. with lattice calculations. In the second part of the talk, I will present ongoing work on matching calculations between the LEFT framework and a scheme that can be implemented on the lattice.