Title: The Cavity Shift of Electron g-2
Speaker: Kevin Zhou
Abstract:
The electron magnetic moment is the most precisely measured property of any fundamental particle. Though its value in free space has been calculated very precisely, in practice the electron is trapped within a conducting cavity, which modifies the mode structure of the electromagnetic field. In quantum electrodynamics, the "cavity shift" is divergent, but standard renormalization techniques are inapplicable as the cavity breaks all symmetries. I will show how one can use contour integration techniques to cancel the divergences analytically, yielding the one-loop cavity shift for spherical and cylindrical cavities. This result can improve the calibration of current and future g-2 experiments. Time permitting, I will also discuss the subtleties of calculating g-2 in the presence of background fields, such as those of ultralight dark matter.