"In this two part work we prove that for every finitely generated subgroup Out(Fn), either is virtually abelian or H2 b (;R) contains a vector space embedding of 1. The method uses actions on hyperbolic spaces. In Part I we focus on the case of infinite lamination subgroups -those for which the set of all attracting laminations of all elements of is an infinite set-using actions on free splitting complexes of free groups. In Part II we focus on finite lamination subgroups and on the construction of useful new hyperbolic actions of those subgroups"-- Provided by publisher.
Michael Handel, CUNY Lehman College, New York, New York.
Lee Mosher, Rutgers University-Newark, New Jersey.
