Reflection Symmetry, APS Boundary Conditions, and Equivariant Spectral Flow on a Warped Cylinder
This paper investigates reflection symmetry and Atiyah-Patodi-Singer boundary conditions for twisted Dirac operators on a warped cylinder, establishing that reflection compatibility requires a specific holonomy quantization and demonstrating how spectral flow decomposes into equivariant or mod-two invariants depending on whether the holonomy is fixed or varying.