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arXiv · 2106.16010

On the Torelli Lie algebra

Alexander Kupers·Oscar Randal-Williams
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Abstract

We prove two theorems about the Malcev Lie algebra associated to the Torelli group of a surface of genus $g$: stably, it is Koszul and the kernel of the Johnson homomorphism consists only of trivial $Sp_{2g}(\mathbb{Z})$-representations lying in the centre.

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Alexander Kupers, Oscar Randal-Williams. 2021-06-30. On the Torelli Lie algebra. https://arxiv.org/abs/2106.16010

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