2000 character limit reached
The cup product of Brooks quasimorphisms (1710.02392v2)
Published 6 Oct 2017 in math.GR and math.GT
Abstract: We prove the vanishing of the cup product of the bounded cohomology classes associated to any two Brooks quasimorphisms on the free group. This is a consequence of the vanishing of the square of a universal class for tree automorphism groups.