Events & Seminars

2018 Jan 09

Dynamics Lunch: Raimundo Briceno (TAU) "A Breiman type theorem for Gibbs measures"

12:00pm to 1:00pm

We will review a Breiman type theorem for Gibbs measures due to Gurevich and Tempelman. For a translation invariant Gibbs measure on a suitable translation invariant configuration set X \subset S^G, where G is an amenable group and S is a finite set, we will prove the convergence of the Shannon-McMillan-Breiman ratio on a specific subset of "generic" configurations. Provided that the above Gibbs measure exists, we also prove the convergence in the definition of pressure and the fact that this Gibbs measure is an equilibrium state.
2018 Jan 02

Dynamics Lunch: Ohad Feldheim (HUJI) "Finitely dependent proper colouring of Z"

12:00pm to 1:00pm

An M-dependent process X(n) on the integers, is a process for which every event concerning with X(-1),X(-2),... is independent from every event concerning with X(M),X(M+1),... Such processes play an important role both as scaling limits of physical systems and as a tool in approximating other processes. A question that has risen independently in several contexts is: "is there an M dependent proper colouring of the integer lattice for some finite M?"
2017 Dec 05

Dynamics Lunch: Jon Aaronson (TA) "Title: "Classical probability theory" for processes generated by expanding C^2 interval maps via quasicompactness."

12:00pm to 1:00pm

Abstract: It was noticed in the 30's by Doeblin & Forte that Markov operators with "chains with complete connections" act quasi-compactly on the Lipschitz functions. These are operators like the transfer operators of certain expanding C^2 interval maps (e.g. the square of Gauss map). It is folklore that stochastic processes generated by smooth observables under these maps satisfy many of the results of "classical probability theory" (e.g. CLT, Chernoff inequality). I'll try to explain some of this in a "lunchtime" mode.
2018 Jan 11

Basic Notions: Michael Hopkins (Harvard) - Homotopy theory and algebraic vector bundles

4:00pm to 5:15pm


Einstein 2
Abstract: This talk will describe joint work with Aravind Asok and Jean Fasel using the methods of homotopy theory to construct new examples of algebraic vector bundles. I will describe a natural conjecture which, if true, implies that over the complex numbers the classification of algebraic vector bundles over smooth affine varieties admitting an algebraic cell decomposition coincides with the classification of topological complex vector bundles.