S. Pace: "Classifying disordering transitions using generalized symmetries" (MIT)

Given an ordered phase of matter (e.g., a superfluid, magnet, etc.), the defects of the order parameter (e.g., vortices, skyrmions, etc.) play a crucial role in driving phase transitions to disordered phases. While such neighboring phases are often trivial, there are known examples of disordering transitions for which the disordered phase is nontrivial and the defects of the order parameter become deconfined fractionalized excitations. In this talk, we will present a classification scheme for such exotic disordered phases of matter whose only input is the microscopic symmetry G and its spontaneous symmetry-breaking pattern G -> H < G in the ordered phase. The hero of this classification is generalized symmetries, which appear as emergent symmetries in ordered phases and whose spontaneous breaking drives the transition into the exotic disordered phases. Instead of diving into the abstract mathematical classification, this talk will emphasize pedagogy by reviewing the exciting developments of generalized symmetries within the past few years and contextualizing the classification within simple nontrivial examples. [based on https://arxiv.org/abs/2308.05730 and https://arxiv.org/abs/2310.08554]