Abstract
We prove that any isometry of the graph of cyclic splittings of a finitely generated free group \(F_N\) of rank \(N\ge 3\) is induced by an outer automorphism of \(F_N\). The same statement also applies to the graphs of maximally-cyclic splittings, and of very small splittings.
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Acknowledgments
This work started during the programme “The Geometry of Outer space: Investigated through its analogy with Teichmueller space” held at Aix-Marseille Université during Summer 2013. We are greatly indebted to the organizers of this event. We would also like to thank Brian Mann for inspiring conversations we had there.
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Horbez, C., Wade, R.D. Automorphisms of graphs of cyclic splittings of free groups. Geom Dedicata 178, 171–187 (2015). https://doi.org/10.1007/s10711-015-0051-2
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DOI: https://doi.org/10.1007/s10711-015-0051-2