356 citations · 2.7k across the 47 of their papers we have counts for
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Fusion Category Symmetry I: Anomaly In-Flow and Gapped Phases
Ryan Thorngren, Yifan Wang
We study generalized discrete symmetries of quantum field theories in 1+1D generated by topological defect lines with no inverse. In particular, we describe 't Hooft anomalies and…
Anomaly Matching in the Symmetry Broken Phase: Domain Walls, CPT, and the Smith Isomorphism
Itamar Hason, Zohar Komargodski, Ryan Thorngren
Symmetries in Quantum Field Theory may have 't Hooft anomalies. If the symmetry is unbroken in the vacuum, the anomaly implies a nontrivial low-energy limit, such as gapless modes…
Topological theory of Lieb-Schultz-Mattis theorems in quantum spin systems
Dominic V. Else, Ryan Thorngren
The Lieb-Schultz-Mattis (LSM) theorem states that a spin system with translation and spin rotation symmetry and half-integer spin per unit cell does not admit a gapped symmetric gr…
Gapless topological phases and symmetry-enriched quantum criticality
Ruben Verresen, Ryan Thorngren, Nick G. Jones +1
We introduce topological invariants for gapless systems and study the associated boundary phenomena. More generally, the symmetry properties of the low-energy conformal field theor…