The Geometry of Loop Spaces II: Characteristic Classes
  Using the Wodzicki residue, we build Wodzicki-Chern-Simons (WCS) classes in $H^{2k-1}(LM)$ associated to the residue Chern character on the loop space $LM$ of a Riemannian manifold $M^{2k-1}$. These WCS classes are associated to the $L^2$ connection and the Sobolev $s=1$ connections on $LM.$ The WCS classes detect several families of 5-manifolds whose diffeomorphism group has infinite fundamental group. These manifolds are the total spaces of the circle bundles associated to a multiple $p\omega, |p|\gg 0$, of the K\"ahler form $\omega$ over an integral K\"ahler surface. 
Yoshiaki Maeda, Steven Rosenberg, Fabi\'an Torres-Ardila
math.DG