1:30 pm MCP 201
Symmetries of field theories.
Asked the question “what sorts of symmetries are allowed in quantum mechanics?” you may answer with “some sort of representations acting on the Hilbert space”. However, a little more thought will tell you that you are allowed things like projective representations. But what else? What about things like semi-linear representations? In this talk we will answer the question “what else” through a generic framework which, in the same breath, allows us to study generalized symmetries, and symmetries in more generic (topological) field theories. The last part of the talk will take us on a related tangent of defining `t Hooft anomalies and their counterpart `t Hooft ambiguities. This talk is based on the paper “Generalized symmetries of topological field theories” (arXiv:2209.13524) with Ben Gripaios and Oscar Randal-Williams. However, much, if not all, the `abstract nonsense’ present in this paper will be left out for this talk.