1. A mathematical theory of topological invariants of quantum spin systems
- Author
-
Artymowicz, Adam, Kapustin, Anton, and Yang, Bowen
- Subjects
Mathematical Physics ,Condensed Matter - Strongly Correlated Electrons ,Mathematics - Quantum Algebra - Abstract
We show that Hall conductance and its non-abelian and higher-dimensional analogs are obstructions to promoting a symmetry of a state to a gauge symmetry. To do this, we define a local Lie algebra over a Grothendieck site as a pre-cosheaf of Lie algebras with additional properties and propose that a gauge symmetry should be described by such an object. We show that infinitesimal symmetries of a gapped state of a quantum spin system form a local Lie algebra over a site of semilinear sets and use it to construct topological invariants of the state. Our construction applies to lattice systems on arbitrary asymptotically conical subsets of a Euclidean space including those which cannot be studied using field theory., Comment: 45 pages. v2: typos corrected, other minor changes
- Published
- 2024