A New Lattice Action for Studying Topological Charge
  We review our recent proposal for a new lattice action for non-abelian gauge theories which reduces short-range lattice artifacts in the computation of the topological susceptibility. The standard Wilson action is replaced by the Wilson action of a gauge covariant interpolation of the original fields to a finer lattice. We illustrate the improved behavior of a same-philosophy new lattice action in the $O(3)$ $\sigma$-model in two dimensions. 
Pilar Hernandez, Raman Sundrum (Harvard University)