Martedi` 2 Ottobre, ore 14.00 Aula di Consiglio, Dipartimento di Matematica, La Sapienza Speaker: F. Patras (University of Nice) Title: Revisiting chaos expansions and Wick products Abstract: Recently, the interest in the structure of cumulants and Wick products for non-Gaussian variables has been revived, since they both play important roles in M. Hairer’s theory of regularity structures. We present a new approach to the theory based on tools (group actions, Hopf algebras) that allow to understand the theory of Wick products as a deformation, a presentation from which many of their properties follow easily. We also discuss how these ideas appear in the theory of regularity structures. Based on j.w. with K. Ebrahimi-Fard, N. Tapia, L. Zambotti. Cordiali saluti Alessandra Faggionato ************************************************* Prof. Alessandra Faggionato http://www1.mat.uniroma1.it/~faggionato/ Department of Mathematics University "La Sapienza" Piazzale Aldo Moro, 5 00185 - Rome Office 5, Phone (0039) 06 49913252 *************************************************