no code implementations • 31 Dec 2020 • Ryan Thorngren, Yifan Wang
We then recast the problem in terms of symmetry defects and find the same conclusions for anomalies of discrete and orientation-reversing global symmetries, up to the conjecture that global gravitational anomalies, which may not be associated with any diffeomorphism symmetry, also forbid the existence of boundary conditions.
High Energy Physics - Theory Strongly Correlated Electrons
no code implementations • 18 Jul 2019 • 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 ground state lacking fractionalized excitations.
Strongly Correlated Electrons Mathematical Physics Mathematical Physics Quantum Physics