L2 dimensions of spaces of braid-invariant harmonic forms
  Let X be a Riemannian manifold endowed with a co-compact isometric action of an infinite discrete group. We consider L2 spaces of harmonic vector-valued forms on the product manifold X^N, which are invariant with respect to an action of the braid group B_N, and compute their von Neumann dimensions (the braided L2- Betti numbers) 
Alexei Daletskii, Alexander Kalyuzhnyi
math.FA math.OA