Khovanov homology for 4-manifolds and the blob complex
Channel: Scott Morrison
Date: 2012-09-18

I'll explain a recipe (joint with Kevin Walker) for defining vector-space valued invariants of 4-manifolds from Khovanov homology. There are some obstacles, forcing us to work in characteristic 2 for now. The blob complex (also joint with Kevin Walker) generalizes this to a sequence of homology groups for each 4-manifold (the original invariant being H_0), which may reflect the familiar long exact sequences computing the Khovanov homology of links.