Higher representations for extended operators

Thomas Bartsch; Mathew Bullimore; Andrea Grigoletto

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arXiv · 2304.03789

Higher representations for extended operators

Thomas Bartsch·Mathew Bullimore·Andrea Grigoletto

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Abstract

It is known that local operators in quantum field theory transform in representations of ordinary global symmetry groups. The purpose of this paper is to generalise this statement to extended operators such as line and surface defects. We explain that $(n-1)$-dimensional operators transform in $n$-representations of a finite invertible or group-like symmetry and thoroughly explore this statement for $n = 1,2,3$. We therefore propose higher representation theory as the natural framework to describe the action of symmetries on the extended operator content in quantum field theory.

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Thomas Bartsch, Mathew Bullimore, Andrea Grigoletto. 2023-04-07. Higher representations for extended operators. https://arxiv.org/abs/2304.03789

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