Commensurations of subgroups of Out(FN)
A theorem of Farb and Handel [FH07] asserts that for N ≥ 4, the natural inclusion from Out(FN ) into its abstract commensurator is an isomorphism. We give a new proof of their result, which enables us to generalize it to the case where N = 3. More generally, we give sufficient conditions on a subgro...
| Main Authors: | , |
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| 格式: | Journal article |
| 語言: | English |
| 出版: |
American Mathematical Society
2020
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