Automorphisms of Free Groups with Boundaries
نویسندگان
چکیده
The automorphisms of free groups with boundaries form a family of groups An,k closely related to mapping class groups, with the standard automorphisms of free groups as An,0 and (essentially) the symmetric automorphisms of free groups as A0,k . We construct a contractible space Ln,k on which An,k acts with finite stabilizers and finite quotient space and deduce a range for the virtual cohomological dimension of An,k . We also give a presentation of the groups and calculate their first homology group. AMS Classification 20F65, 20F28; 20F05
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