# Generalized Symmetries and Axion Standard Model

- Institution: CERN
- Department: TH String Theory Seminar
- Speaker: Ho Tat Lam
- Year: 2024
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3007682)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

The Standard Model gauge group has an ambiguity in its global form, which is closely related to a Z_6 one-form global symmetry. In this talk, we will discuss how this ambiguity affects the simplest model of QCD axions - a single axion coupled to the Standard Model. Assuming the absence of axion domain wall problem, we derive a lower bound on the axion-photon coupling. We will then discuss the fate of this Z_6 one-form global symmetry in the axion Standard Model. Depending on the details, the symmetry can be part of a higher-group or a non-invertible symmetry. Using this symmetry, we argue for a lower bound on the hypercharge magnetic monopole mass and the axion string tension. .

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## Lectures

1. [Generalized Symmetries and Axion Standard Model](https://invisiblenetwork.ai/learn/cern/3007682/273a8b36b0dd), 1 h 6 min (CERN's player)