PIRSA:23030078

Symmetry Lost and Found

APA

Shao, S. (2023). Symmetry Lost and Found. Perimeter Institute for Theoretical Physics. http://pirsa.org/23030078

MLA

Shao, Shu-Heng. Symmetry Lost and Found. Perimeter Institute for Theoretical Physics, Mar. 28, 2023, http://pirsa.org/23030078

BibTex

          @misc{ scivideos_PIRSA:23030078,
            doi = {},
            url = {http://pirsa.org/23030078},
            author = {Shao, Shu-Heng},
            keywords = {Quantum Fields and Strings},
            language = {en},
            title = {Symmetry Lost and Found},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2023},
            month = {mar},
            note = {PIRSA:23030078 see, \url{https://scivideos.org/index.php/PIRSA/23030078}}
          }
          

Shu-Heng Shao Stony Brook University

Source Repository PIRSA
Talk Type Scientific Series

Abstract

In massless QED, we find that the classical U(1) axial symmetry is not completely broken by the Adler-Bell-Jackiw anomaly. Rather, it is resurrected as a generalized global symmetry labeled by the rational numbers. Intuitively, this new global symmetry in QED is a composition of the naive axial rotation and a fractional quantum Hall state. The conserved symmetry operators do not obey a group multiplication law, but a non-invertible fusion algebra. We further generalize our construction to QCD, and show that the neutral pion decay can be derived from a matching condition of the non-invertible global symmetry. Finally, we find a non-invertible Gauss law in axion-Maxwell theory.

Zoom link:  https://pitp.zoom.us/j/93832561140?pwd=czFFSkVvYS9RbXRjOTJPQVFhL2hGZz09