Colloquium- “Topological Interactions in Quantum Field Theory” with Prof. Aleksey Cherman (University of Minnesota)
Colloquium
April 22, 2025
3:30 PM - 4:30 PM
Location
138 2SES
Calendar
Download iCal FileProf. Aleksey Cherman
Department of Physics
University of Minnesota
Sponsored by the Laboratory for Quantum Theory at the Extremes (LQuTE)
Abstract: Many quantum field theories, including ones that play a prominent role in our description of nature, have interesting topological interactions. The associated coupling constants are periodic and are called theta angles. But how many theta angles does a given quantum field theory have? This is perhaps the simplest question one can ask about theta angles, and it has a by-now standard answer developed by physicists and mathematicians. However, it turns out that the standard approach to counting theta angles is incomplete, essentially because it does not adopt a sufficiently broad definition of the notion of theta angles. I'll explain a simple counter-example to the standard classification of theta angles, which we've called a "Cheshire theta angle", which has potentially interesting physical implications. I'll then briefly advertise a more flexible view on what theta angles actually are, and use this to motivate an improved classification of theta angles.
Date posted
Apr 7, 2025
Date updated
Apr 7, 2025