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arXiv · 1307.1495

A note on subfactor projections

Samuel J. Taylor
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Abstract

We extend some results of [BF12] on subfactor projections to show that the projection of a free factor B to the free factor complex of the free factor A is well-defined with uniformly bound diameter, unless either A is contained in B or A and B are vertex stabilizers of a single splitting of F_n, i.e. they are disjoint. These projections are shown to satisfy properties analogous to subsurface projections, and we give as an application a construction of fully irreducible outer automorphisms using the Bounded Geodesic Image Theorem.

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Samuel J. Taylor. 2013-07-04. A note on subfactor projections. https://doi.org/10.2140/agt.2014.14.805

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