High Energy Phenomenology Seminar: Kevin Zhang (University of California, Santa Barbara) "Magic Zeroes and Hidden Symmetries"
- Event Type
- Seminar/Symposium
- Sponsor
- Department of Physics
- Location
- Room 464
- Date
- Sep 23, 2022 11:00 am
- Speaker
- Kevin Zhang
- Contact
- Brandy Koebbe
- BKOEBBE@ILLINOIS.EDU
- Views
- 32
- Originating Calendar
- Physics - High Energy Physics Seminar
Selection rules arising from accidental or broken symmetries may be sufficiently obscure that their agency is hidden, leading to the appearance of “magic zeroes” – quantities that are suppressed without apparent recourse to a symmetry explanation. Magic zeroes and their corresponding hidden symmetries may shed new light on parametric hierarchies in the Standard Model and beyond. We identify the hidden symmetry responsible for a recently-discovered magic zero, the vanishing of the putative leading contribution to the anomalous dipole moments of the muon upon integrating out weak doublet and singlet vector-like fermions. Some of the tools involved – spurion analysis leveraging discrete symmetries of the free theory, field redefinitions, spectator fields, and non-supersymmetric non-renormalization theorems – may prove useful in the hunt for new magic zeroes and their hidden symmetries.