Abstract
Let M be an oriented smooth manifold and Homeo(M, ω) the group of measure preserving homeomorphisms of M, where ω is a finite measure induced by a volume form. In this paper, we define volume and Euler classes in bounded cohomology of an infinite dimensional transformation group Homeo0(M, ω) and Homeo+(M, ω), respectively, and in several cases prove their non-triviality. More precisely, we define: • Volume classes in Hnb ( Homeo0(M, ω)), where M is a hyperbolic manifold of dimension n. • Euler classes in H2b ( Homeo+ (S, ω)), where S is an oriented closed hyperbolic surface. We show that Euler classes have positive norms for any closed hyperbolic surface and volume classes have positive norms for all hyperbolic surfaces and certain hyperbolic 3-manifolds; hence, they are non-trivial.
| Original language | American English |
|---|---|
| Journal | Glasgow Mathematical Journal |
| DOIs | |
| State | Accepted/In press - 1 Jan 2024 |
Keywords
- bounded cohomology
- characteristic classes
- euler class
- homeomomorphisms of manifolds
- mapping class group
- volume class
All Science Journal Classification (ASJC) codes
- General Mathematics