Bobby W. Ramsey | Searcharxiv

arXiv2016

Extending Properties to Relatively Hyperbolic Groups

Consider a finitely generated group $G$ that is relatively hyperbolic with respect to a family of subgroups $H_1, ..., H_n$. We present an axiomatic approach to the problem of extending metric properties from the subgroups $H_i$ to the full group $G$. We use this to show that both (weak) finite decomposition complexity and straight finite decomposition complexity are extendable properties. We also discuss the equivalence of two notions of straight finite decomposition complexity.

math.GR↗

arXiv2012

A Spectral sequence for polynomially bounded cohomology

We construct an analogue of the Lyndon-Hochschild-Serre spectral sequence in the context of polynomial cohomology, for group extensions. If G is an extension of Q by H, then the spectral sequence converges to the polynomial cohomology of G. For the polynomial extensions of Noskov with normal subgroup isocohomological, the E_2 term is the polynomial cohomology of Q with coefficients in the polynomial cohomology of H. When both Q and H are isocohomological G must be as well. By referencing results of Connes-Moscovici and Noskov, if Q and H are both isocohomological and have the Rapid Decay property of Jolissaint, then G satisfies the Novikov Conjecture.

math.KT↗