Seminars

Speaker: Ryohei Kobayashi (University of Maryland)

Date & Time: 10am, July 25, 2022.

Title: Symmetry-preserving boundary of (2+1)D fractional quantum Hall states

Abstract:

We investigate symmetry-preserving gapped boundary of (2+1)D topological phases with global symmetry, which can be either bosonic or fermionic. We develop a general algebraic description for gapped boundary condition for symmetry-enriched or fermionic topological phases, extending the framework of Lagrangian algebra anyon for bosonic phases without symmetry. We then focus on application to the case with U(1) symmetry. We derive new obstructions to symmetry-preserving gapped boundary for U(1)f symmetric (2+1)D fermionic topological phases, which are beyond chiral central charge and electric Hall conductivity.