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arXiv · 1307.6750

The conjugacy problem in extensions of Thompson's group F

José Burillo·Francesco Matucci·Enric Ventura
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Abstract

We solve the twisted conjugacy problem on Thompson's group F. We also exhibit orbit undecidable subgroups of Aut(F), and give a proof that Aut(F) and Aut_+(F) are orbit decidable provided a certain conjecture on Thompson's group T is true. By using general criteria introduced by Bogopolski, Martino and Ventura in [5], we construct a family of free extensions of F where the conjugacy problem is unsolvable. As a byproduct of our techniques, we give a new proof of a result of Bleak-Fel'shtyn-Goncalves in [4] showing that F has property R_\infty, and which can be extended to show that Thompson's group T also has property R_\infty.

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José Burillo, Francesco Matucci, Enric Ventura. 2013-09-07. The conjugacy problem in extensions of Thompson's group F. https://arxiv.org/abs/1307.6750

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