Cyclic Cohomology of Etale Groupoids; The General Case

Abstract

We give a general method for computing the cyclic cohomology of crossed products by etale groupoids, extending the Feigin-Tsygan-Nistor spectral sequences. In particular we extend the computations performed by Brylinski, Burghelea,Connes and Nistor for the convolution algebra -of compactly supported smooth functions- of an etale groupoid, removing the Hausdorffness assumption and including the computation of the hyperbolic components. Examples like group actions on manifolds and foliations are considered.