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arXiv · 1509.02939

Reeb Dynamics of the Link of the $A_n$ Singularity

Leonardo Enrique Abbrescia·Irit Huq-Kuruvilla·Jo Nelson·Nawaz John Sultani
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Abstract

The link of the $A_n$ singularity, $L_{A_n} \subset \mathbb{C}^3$ admits a natural contact structure $ξ_0$ coming from the set of complex tangencies. The canonical contact form $α_0$ associated to $ξ_0$ is degenerate and thus has no isolated Reeb orbits. We show that there is a nondegenerate contact form for a contact structure equivalent to $ξ_0$ that has two isolated simple periodic Reeb orbits. We compute the Conley-Zehnder index of these simple orbits and their iterates. From these calculations we compute the positive $S^1$-equivariant symplectic homology groups for $\left(L_{A_n}, ξ_0 \right)$. In addition, we prove that $\left(L_{A_n}, ξ_0 \right)$ is contactomorphic to the Lens space $L(n+1,n)$, equipped with its canonical contact structure $ξ_{std}$.

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Leonardo Enrique Abbrescia, Irit Huq-Kuruvilla, Jo Nelson, Nawaz John Sultani. 2016-06-14. Reeb Dynamics of the Link of the $A_n$ Singularity. https://doi.org/10.2140/involve.2017.10.417

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