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Clusters, currents and Whitehead's algorithm

Ilya Kapovich
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Abstract

Using geodesic currents, we provide a theoretical justification for some of the experimental results regarding the behavior of Whitehead's algorithm on non-minimal inputs, that were obtained by Haralick, Miasnikov and Myasnikov via pattern recognition methods. In particular we prove that the images of "random" elements of a free group $F$ under the automorphisms of $F$ form "clusters" that share similar normalized Whitehead graphs and similar behavior with respect to Whitehead's algorithm.

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Ilya Kapovich. 2006-09-12. Clusters, currents and Whitehead's algorithm. https://arxiv.org/abs/math/0511478

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