“…[
5–8 ] A number of recent works have shown that symmetry operators without inverses (and which are therefore not elements of any group, but should rather be thought of in categorical terms) are also very common in higher dimensional theories. [
9–26 ] In this paper we will focus on one class of theories where such non‐invertible symmetries appear:
theories with gauge group
,
and
. [
14 ] The details are a little different in the three cases, so in this introduction we will focus on the
case for concreteness.…”