Legendrian framings for two-bridge links

Sebastian Baader; Masaharu Ishikawa

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arXiv · 0910.0355

Legendrian framings for two-bridge links

Sebastian Baader·Masaharu Ishikawa

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Abstract

We define the Thurston-Bennequin polytope of a two-component link as the convex hull of all pairs of integers that arise as framings of a Legendrian representative. The main result of this paper is a description of the Thurston-Bennequin polytope for two-bridge links. As an application, we construct non-quasipositive surfaces in $\R^3$ all whose sub-annuli are quasipositive.

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Sebastian Baader, Masaharu Ishikawa. 2009-10-02. Legendrian framings for two-bridge links. https://arxiv.org/abs/0910.0355

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