In algebraic geometry, there is a Hodge to de Rham spectral sequence and the statement of the sufficient conditions when it degenerates. Maxim Kontsevich has conjectured an extension of this to noncommutative algebraic geometry based on -categories. A somewhat weaker case, in the framework of dg-categories has been proved by Dmitri Kaledin. Although the conjecture is in characteristic zero, Kaledin has used a method in positive characteristic, combining the cyclic homology with ideas from the one of the proofs of the classical Hodge-dR ss degeneration with positive characteristic methods due Pierre Deligne and Luc Illusie, involving Frobenius automorphism and so-called Cartier operator. This is one of the most nontrivial facts in noncommutative geometry.