AbstractIt is known that 2d (spatial dimension) symmetry protected topological (SPT) orders and symmetry enriched topological (SET) orders with finite onsite symmetries can be characterized by using the idea of gauging the symmetry and minimal modular extensions. In this talk, I will introduce another characterization of SPT/SET orders in all dimensions based on the boundary-bulk relation. In 1...
AbstractIt would be useful to deal with complex geometry when examining quantum gravity as in the case of no-boundary proposal by Hartle and Hawking. However, there would be too many saddles for complexified gravity, and it is necessary to determine which are allowable geometries in the sense of Witten. We consider three-ddimensional gravity theory with positive consmological constant described...