Geometry & Topology

Rounding corners of polygons and the embedded contact homology of $T^3$

Michael Hutchings and Michael G Sullivan

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The embedded contact homology (ECH) of a 3–manifold with a contact form is a variant of Eliashberg–Givental–Hofer’s symplectic field theory, which counts certain embedded J–holomorphic curves in the symplectization. We show that the ECH of T3 is computed by a combinatorial chain complex which is generated by labeled convex polygons in the plane with vertices at lattice points, and whose differential involves “rounding corners”. We compute the homology of this combinatorial chain complex. The answer agrees with the Ozsváth–Szabó Floer homology HF+(T3).

Article information

Geom. Topol., Volume 10, Number 1 (2006), 169-266.

Received: 5 October 2004
Accepted: 25 January 2006
First available in Project Euclid: 20 December 2017

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Zentralblatt MATH identifier

embedded contact homology Floer homology


Hutchings, Michael; Sullivan, Michael G. Rounding corners of polygons and the embedded contact homology of $T^3$. Geom. Topol. 10 (2006), no. 1, 169--266. doi:10.2140/gt.2006.10.169.

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