Khovanov homology, open books, and tight contact structures

John A. Baldwin; Olga Plamenevskaya

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arXiv · 0808.2336

Khovanov homology, open books, and tight contact structures

John A. Baldwin·Olga Plamenevskaya

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Abstract

We define the reduced Khovanov homology of an open book (S,h), and we identify a distinguished "contact element" in this group which may be used to establish the tightness or non-fillability of contact structures compatible with (S,h). Our construction generalizes the relationship between the reduced Khovanov homology of a link and the Heegaard Floer homology of its branched double cover. As an application, we give combinatorial proofs of tightness for several contact structures which are not Stein-fillable. Lastly, we investigate a comultiplication structure on the reduced Khovanov homology of an open book which parallels the comultiplication on Heegaard Floer homology defined previously by the first author.

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John A. Baldwin, Olga Plamenevskaya. 2008-09-26. Khovanov homology, open books, and tight contact structures. https://arxiv.org/abs/0808.2336

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