Chain flaring and $L^{2}$-torsion of free-by-cyclic groups

Matt Clay

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arXiv · 2107.09775

Chain flaring and $L^{2}$-torsion of free-by-cyclic groups

Matt Clay

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Abstract

We introduce a condition on the monodromy of a free-by-cyclic group, $G_ϕ$, called the chain flare condition, that implies that the $L^2$-torsion, $ρ^{(2)}(G_ϕ)$, is non-zero. We conjecture that this condition holds whenever the monodromy is exponentially growing.

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Matt Clay. 2021-07-20. Chain flaring and $L^{2}$-torsion of free-by-cyclic groups. https://arxiv.org/abs/2107.09775

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