Vanishing theorems for the basic cohomology of Riemannian foliations.
We construct a certain algebro-geometric version of the free loop space for a complex algebraic variety X. This is an ind-scheme containing the scheme of formal arcs in X as studied by Kontsevich and Denef-Loeser. We describe the chiral de Rham complex of Malikov, Schechtman and Vaintrob in terms of the space of formal distributions on supported in . We also show that possesses a factorization structure: a certain non-linear version of a vertex algebra structure. This explains the heuristic...