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arXiv · 0908.1255

Subgroup classification in Out(F_n)

Michael Handel·Lee Mosher
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Abstract

For any subgroup H of Out(F_n), either H has a finite index subgroup that fixes the conjugacy class of some proper, nontrivial free factor of F_n, or H contains a fully irreducible element phi, meaning that no positive power of phi fixes the conjugacy class of any proper, nontrivial free factor of F_n.

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Michael Handel, Lee Mosher. 2009-08-09. Subgroup classification in Out(F_n). https://arxiv.org/abs/0908.1255

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