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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
E-Mail
BKOEBBE@ILLINOIS.EDU
Views
18
Originating Calendar
Physics - High Energy Phenomenology 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.

 
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