Date/Time
Date(s) - 19/11/2025
10:30 am - 11:30 am

BSB 108

Dr. Yoni Kahn
Assistant Professor
University of Toronto

Profile: https://www.physics.utoronto.ca/members/kahn-yonatan-yoni/

TITLE: Quantum or Classical? Cavity Shifts in Electron Magnetic Moment Measurements

ABSTRACT:

The magnetic moment of the electron is the most precisely known property of a fundamental particle, and its measurement currently stands at sub-parts-per-trillion precision. Pushing this measurement to another decimal place of precision requires a rigorous treatment of boundary condition effects on the electron energy levels, known as the cavity shift. I will present a new calculation of this effect in both relativistic and non-relativistic quantum mechanics, and show — perhaps surprisingly — that these quantum calculations exactly reproduce decades-old calculations of the cavity shift using only classical electrodynamics. Along the way I will relate these computations to the early history of quantum electrodynamics and offer some musings on understanding quantum phenomena with classical reasoning.