In this talk, I will discuss the tension between two well-established facts about gauge theories: that large N gauge theories confine, and that confinement can be understood in terms of 1-form symmetry. It has long been appreciated that in QCD-like theories without fundamental matter, confinement can be given a sharp characterization in terms of symmetry. More recently, such symmetries have been identified as 1-form symmetries, which fit under the broader umbrella of generalized global symmetries. I will discuss obstructions to the existence of a 1-form symmetry in large N QCD, where confinement is nevertheless a sharp notion. I give general arguments valid in any spacetime dimension, and use 2d scalar QCD on the lattice as a concrete example.
Andrew Hanlon