Séance exceptionnelle, mercredi 3 mai 2006 à 14h.<br/>
Orateur : Michael Krivelevich (Tel Aviv University).<br/>
Titre : Sphere packings in R^n through Graph Theory.<br/>

<p>Résumé :<br/>

In this talk I will demonstrate how graph theoretic tools can
be utilized to show that for all sufficiently large n there exist sphere
packings in R^n of density at least cn/2^n, matching up to a constant
factor best known lower bounds for this classical problem of Minkowski.<br>
A joint work with Simon Litsyn (Tel Aviv University) and Alexander
Vardy (University of California at San Diego).