2 papers
math.GT2025
The Euler Class and Flux Homomorphisms under Non-Orientability
KyeongRo Kim, Shuhei Maruyama
For an orientable surface with an area form, there are two invariants of area-preserving dynamics, the flux homomorphism and the Calabi invariant. Tsuboi found a remarkable connect…
math.GT2024
McDuff's secondary class and the Euler class of foliated sphere bundles
Shuhei Maruyama
Tsuboi proved that the Calabi invariant of the closed disk transgresses to the Euler class of foliated circle bundles and suggested looking for its higher-dimensional analog. In th…