Mercredi 1 Février
Heure: 
13:30  15:00 
Lieu: 
Salle B405, bâtiment B, LAGA, Institut Galilée, Université Paris 13 
Résumé: 
Théorie Ergodique et Systèmes Dynamiques  Hausdorff dimension of exact set in metric measure spaces  
Description: 
Prasuna Bandi In Diophantine approximation, it is a classical problem to determine the size of the sets related to psi approximable set for a given nonincreasing function psi. The exact psiapproximable set is the set of numbers that are psiapproximable and not approximable to a better order than psi. Bugeaud determined the Hausdorff dimension of the exact psiapproximable set answering a question posed by Beresnevich, Dickinson, and Velani. We compute the Hausdorff dimension of the exact set in the general setup of Ahlfors regular spaces. Our result applies to approximation by orbits of fixed points of a wide class of discrete groups of isometries acting on the boundary of hyperbolic metric spaces. This is joint work with Anish Ghosh and Debanjan Nandi. 

