TY - JOUR
T1 - Automorphisms of free groups with boundaries
AU - A. Jensen, Craig
AU - Wahl, Nathalie
N1 - Keywords: math.GT; math.AT; 20F65, 20F28, 20F05
PY - 2004
Y1 - 2004
N2 - The automorphisms of free groups with boundaries form a family of groups A_{n,k} closely related to mapping class groups, with the standard automorphisms of free groups as A_{n,0} and (essentially) the symmetric automorphisms of free groups as A_{0,k}. We construct a contractible space L_{n,k} on which A_{n,k} acts with finite stabilizers and finite quotient space and deduce a range for the virtual cohomological dimension of A_{n,k}. We also give a presentation of the groups and calculate their first homology group.
AB - The automorphisms of free groups with boundaries form a family of groups A_{n,k} closely related to mapping class groups, with the standard automorphisms of free groups as A_{n,0} and (essentially) the symmetric automorphisms of free groups as A_{0,k}. We construct a contractible space L_{n,k} on which A_{n,k} acts with finite stabilizers and finite quotient space and deduce a range for the virtual cohomological dimension of A_{n,k}. We also give a presentation of the groups and calculate their first homology group.
M3 - Journal article
VL - 4
SP - 543
EP - 569
JO - Algebr. Geom. Topol.
JF - Algebr. Geom. Topol.
ER -