A bound for rational Thurston-Bennequin invariants

Youlin Li; Zhongtao Wu

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arXiv · 1705.09440

A bound for rational Thurston-Bennequin invariants

Youlin Li·Zhongtao Wu

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Abstract

In this paper, we introduce a rational $\tau$ invariant for rationally null-homologous knots in contact 3-manifolds with nontrivial Ozsv\'{a}th-Szab\'{o} contact invariants. Such an invariant is an upper bound for the sum of rational Thurston-Bennequin invariant and the rational rotation number of the Legendrian representatives of the knot. In the special case of Floer simple knots in L-spaces, we can compute the rational $\tau$ invariants by correction terms.

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Youlin Li, Zhongtao Wu. 2017-05-26. A bound for rational Thurston-Bennequin invariants. https://arxiv.org/abs/1705.09440

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