학술논문

The action of mapping class groups on de Rham quasimorphisms
Document Type
Working Paper
Source
Subject
Mathematics - Geometric Topology
Mathematics - Algebraic Topology
Mathematics - Group Theory
Mathematics - Metric Geometry
57K20 (primary), 20J06, 20F67, 57R19, 20E36 (secondary)
Language
Abstract
We study the action of the mapping class group on the subspace of de Rham classes in the degree-two bounded cohomology of a hyperbolic surface. In particular, we show that the only fixed nontrivial finite-dimensional subspace is the one generated by the Euler class. As a consequence, we get that the action of the mapping class group on the space of de Rham quasimorphisms has no fixed points.
Comment: 21 pages, 4 figures. Comments are welcome!