Jeudi 1er juin 2006, à 14h15.
Orateur : Alexander Barg.
Titre : Spectral approach to linear-programming bounds of coding theory.
The proofs of the basic upper bounds of coding theory obtained within the framework of Delsarte's method (1977) have always had a deus-ex-machina flavor to them in the sense that, being watertight formally, they have altogether resisted geometric interpretation. In a joint work with Dmitry Nogin we have found a new approach to the proofs that ties the underlying functions to eigenvectors of some finite-dimensional operators.