Moduli of graphs and automorphisms of free groups
@article{Culler1986ModuliOG, title={Moduli of graphs and automorphisms of free groups}, author={Marc Culler and Karen Vogtmann}, journal={Inventiones mathematicae}, year={1986}, volume={84}, pages={91-119} }
This paper represents the beginning of an a t tempt to transfer, to the study of outer au tomorphisms of free groups, the powerful geometric techniques that were invented by Thurs ton to study mapping classes of surfaces. Let F, denote the free group of rank n. We will study the g roup Out(F,) of outer au tomorphisms of F, by studying its act ion on a space X, which is analogous to the Teichmtiller space of hyperbol ic metrics on a surface; the points of X, are metric structures on graphs with…
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