January 31 (wednesday)
14.00 – 14.45 Valérie Berthé (Paris VII), « Dendric subshifts and groups »
15.00 – 15.45 Nguyen-Bac Dang, (Orsay) , « Variation of the Hausdorff dimension of limits set and degenerating Schottky groups »
16.15 – 17.00 Bruno Duchesne (Orsay), TBA
Valérie Berthé, « Dendric subshifts and groups »
We discuss a family of symbolic dynamical systems that have remarkable group properties, the family of dendric words. This family includes numerous classical families of symbolic dynamical systems, among others codings of interval exchanges. Their return words form positive basis of the free group. We discuss their dimension groups, which are complete invariants of strong orbit equivalence, andapplications to skew products based on finite groups.
Nguyen Bac Dang, « Variation of the Hausdorff dimension of limits set and degenerating Schottky groups »
In this talk, based on a joint work with Vlerë Mehmeti, I will explain how one can use some techniques in non-Archimedean geometry to study families of degenerating complex Schottky groups. More precisely, each Schottky group comes with a fractal set, obtained as a limit of an orbit, called the limit set. We show that under specific conditions, one can can obtain an asymptotic formula for the Hausdorff dimension of the limit set. If time permits, I will present how certain functions, called Poincare series have very special behavior when one works over non-Archimedean fields.
Organized by Andrei Alpeev, Laurent Bartholdi, Anna Erschler and Panagiotis Tselekidis
Partially supported by ERC Advanced Grant 101097307 (P.I.:Laurent Bartholdi).