Higher-form symmetries and spontaneous symmetry breaking
Ethan Lake
TL;DR
This work extends spontaneous symmetry breaking to theories with higher-form symmetries by formulating a higher Goldstone theorem in which massless $p$-form gauge fields act as Goldstones, and by clarifying boundary conditions, Ward identities, and gauge fixing in these contexts. It establishes a generalized Coleman-Mermin-Wagner result: continuous $p$-form symmetries in $D$ dimensions cannot be spontaneously broken when $p \,\ge\, D-2$, with complementary analyses for continuum, compact, and discrete theories and interpretations via duality. The paper also links higher-form symmetry breaking to confinement diagnostics using Wilson membranes/loops and explores connections to asymptotic symmetries on manifolds with trivial cohomology, outlining how boundary data and nonperturbative effects shape IR behavior. Overall, it provides a coherent framework to understand phase structure, dual descriptions, and boundary phenomena for higher-form symmetries, with implications for topological phases and gauge-theory memory effects. The results suggest rich interplay between symmetry breaking, confinement, duality, and asymptotic symmetries in Abelian gauge theories.
Abstract
We study various aspects of spontaneous symmetry breaking in theories that possess higher-form symmetries, which are symmetries whose charged objects have a dimension $p>0$. We first sketch a proof of a higher version of Goldstone's theorem, and then discuss how boundary conditions and gauge-fixing issues are dealt with in theories with spontaneously broken higher symmetries, focusing in particular on $p$-form $U(1)$ gauge theories. We then elaborate on a generalization of the Coleman-Mermin-Wagner theorem for higher-form symmetries, namely that in spacetime dimension $D$, continuous $p$-form symmetries can never be spontaneously broken if $p\geq D-2$. We also make a few comments on relations between higher symmetries and asymptotic symmetries in Abelian gauge theory.
