AbstractIn this talk, we explain the classificatin of the metric fibration that is a metric analogue of topological fibration introduced by T. Leinster in the study of magnitude. The magnitude of metric spaces, also introduced by Leinster, is an analogy of the Euler characteristic from a viewpoint of enriched category theory. As the Euler characteristic of the usual fibration splits into those ...
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...