Abstract
For N≥3, the abstract commensurators of both Aut(FN) and its Torelli subgroup IAN are isomorphic to Aut(FN) itself.
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Acknowledgements
We thank Mladen Bestvina and Camille Horbez for many fruitful conversations surrounding the material in this paper. We thank Matt Clay for asking about the abstract commensurator of Aut(F2) and for his suggestions concerning its geometry. We also thank the referee for their careful reading and helpful comments. The second author is supported by a University Research Fellowship from the Royal Society.
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Bridson, M.R., Wade, R.D. Commensurations of Aut(FN) and Its Torelli Subgroup. Geom. Funct. Anal. (2024). https://doi.org/10.1007/s00039-024-00681-y
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DOI: https://doi.org/10.1007/s00039-024-00681-y