Joint IAS/Princeton University Symplectic Geometry Seminar

We define an invariant of contact structures in dimension three based on the contact invariant of Ozsvath and Szabo from Heegaard Floer homology. This invariant takes values in $\\mathbb Z_{\\geq0}\\cup\\{\\infty\\}$, is zero for overtwisted contact structures, $\\infty$ for Stein fillable contact structures, and non-decreasing under Legendrian surgery. This is joint work with Cagaty Kutluhan, Jeremy Van Horn-Morris and Andy Wand.