Abstract:
Foams in 3-space are cobordisms between planar graphs that are heavily used in link homology theories. In this talk we'll explain how foam theory can be built from the ground up starting with an evaluation of closed foams, for SL(2) foams, then GL(2) foams, and finally GL(N) foams for any N. The talk is based on joint work with Louis-Hadrien Robert and on L.-H. Robert and Emmanuel Wagner's work on foam evaluation