Bar Natan in the wild

-
Tomasz Mrowka, MIT

This is the first of a two part series on work with Peter Kronheimer.听In this talk I will describe a variant of Instanton Floer homology for knots or more generally webs (embedded trivalent graphs) in 3-manifolds. The interesting twist in the story is introducing a local coefficient group which seems to require the use of webs (rather than knots). For certain specializations of this local system the resulting homology groups admit a spectral sequence whose $E_2$-term is Bar-Natan鈥檚 variant of Khovanov homology providing a geometric interpretation of that theory.听 I鈥檒l try to sketch some of this story.

Kronheimer鈥檚 talk the following week will describe further (potential) applications of these groups.