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arXiv · 2203.03102

The free factor complex and the dualizing module for the automorphism group of a free group

Zachary Himes·Jeremy Miller·Sam Nariman·Andrew Putman
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Abstract

Answering a question of Hatcher-Vogtmann, we prove that the top homology group of the free factor complex is not the dualizing module for $\text{Aut}(F_n)$, at least for $n = 5$.

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Zachary Himes, Jeremy Miller, Sam Nariman, Andrew Putman. 2022-03-07. The free factor complex and the dualizing module for the automorphism group of a free group. https://doi.org/10.1093/imrn/rnac330

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