5 papers · 1 filter
The geometry of branched coverings of hyperbolic manifolds
Ursula Hamenstädt
We discuss geometric properties of covers of closed hyperbolic manifolds of dimension , branched along a totally geodesic codimension two submanifold . The results are…
Submanifold projections and hyperbolicity in
Ursula Hamenstädt, Sebastian Hensel
The free splitting graph of a free group with generators is a hyperbolic -graph which has a geometric realization as a sphere graph in the connected…
Spotted disk and sphere graphs I
Ursula Hamenstädt
The disk graph of a handlebody H of genus g at least 2 with m marked points on the boundary is the graph whose vertices are isotopy classes of disks disjoint from the marked points…
Signature of surface bundles and bounded cohomology
Ursula Hamenstädt
Extending a result of Morita, we show that all tautological classes of the moduli space of genus g curves are bounded. As an application, we obtain that for a surface bundle $E\to…
Isoperimetric inequalities for the handlebody groups
Ursula Hamenstädt, Sebastian Hensel
We show that the mapping class group of a handlebody of genus at least 2 has a Dehn function of at most exponential growth type.