A physicist-friendly reformulation of the Atiyah-Patodi-Singer index (on a lattice)

30 Jul 2021, 02:40
20m
Plenary presentation Invited plenary Plenary

Speaker

Hidenori Fukaya (Osaka Univ.)

Description

The Atiyah-Singer(AS) index theorem on a closed manifold is well understood and appreciated in physics. On the other hand, the Atiyah-Patodi-Singer(APS) index, which is an extension to a manifold with boundary, is physicist-unfriendly, in that it is formulated with a nonlocal boundary condition. Recently we (3 physicists and 3 mathematicians) proved that the same index as APS is obtained from the domain-wall fermion Dirac operator. Our theorem indicates that the index can be expressed without any nonlocal conditions, in such a physicist-friendly way that application to the lattice gauge theory is straightforward. The domain-wall fermion provides a natural mathematical foundation for understanding the bulk-edge correspondence of the anomaly inflow.

Primary author

Hidenori Fukaya (Osaka Univ.)

Presentation materials