Abstract
Let Y → X be a finite normal cover of a wedge of n ≥ 3 circles. We prove that for any nonzero v ∈ H 1(Y; Q) there exists a lift \(\widetilde F\) to Y of a basepoint-preserving homotopy equivalence F: X → X such that the set of iterates \(\left\{ {{{\widetilde F}^d}\left( v \right)} \right\}:d \in \mathbb{Z} \subseteq {H_1}\left( {Y,\mathbb{Q}} \right)\) is infinite. The main achievement of this paper is the use of representation theory to prove the existence of a purely topological object that seems to be inaccessible via topology.
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The first author gratefully acknowledges support from the National Science Foundation.
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Farb, B., Hensel, S. Moving homology classes in finite covers of graphs. Isr. J. Math. 220, 605–615 (2017). https://doi.org/10.1007/s11856-017-1528-5
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DOI: https://doi.org/10.1007/s11856-017-1528-5