In 1927 G. Birkhoff conjectured that if a billiard in a strictly convex smoothdomain is integrable, the domain has to be an ellipse (or a circle). Theconjecture is still wide open, and presents remarkable relations with openquestions in inverse…
Eventi
On recent results of extreme value theory applied to dynamical systems – Sandro Vaienti (CPT Marseille)
We give a review of a few recent results of extreme value theory applied to random dynamical systems and to coupled lattice maps…
Torus surgery in the 4-sphere – Kyle Larson (Università di Austin (Texas))
I will introduce the operation of torus surgery in the 4-sphere, and describe some recent results concerning which 4-manifolds can beproduced in this way and the uniqueness of such descriptions. As motivation I will discuss analogous results and…
Local Limit Theorem for Sums of Independent Random Variables – Dimitry Dolgopyat (University of Maryland)
We provide sufficient conditions for a sum of independent random variables to satisfy a local limit theorem. In particular it is sufficient that the variables be uniformly bounded.…
Non-local isoperimetric problems – Berardo Ruffini (CMAP, Ecole Polytechnique)
The talk is aimed to present some recent results about strong version of non-local isoperimetric isoperimetric problems, that is, problems involving the minimisation of the fractional perimeter. Namely, we will see how to prove a strong version of…
Fibrazioni ellittiche di varieta’ di Calabi-Yau 3folds, algebre di Lie e rappresentazioni collegate – Antonella Grassi (University of Pennsylvania)
I punti doppi razionali, (singolarita’ di Klein o du Val) sono classificati da diagrammi di Dynkin di certe algebre di Lie; queste sono anche le singolarita’ dei modelli di Weierstrass di superfici ellittiche. La struttura di algebra di Lie si…
A ridiculously short crash course in infinite ergodic theory with a view towards the question of mixing – Marco Lenci (Università di Bologna)
This is a two-hour seminar, with the first part dedicated to introducing basic concepts in infinite ergodic theory.…
Liouville integrability: an effective Morales-Ramis-Simo theorem – Thomas Dreyfus (Institut de Mathématiques de Toulouse)
Morales-Ramis theorem roughly states as follows: Given an Hamiltonian system, we may linearize it to obtain the variational equation. Then, we associate to the variational equation a group, the differential Galois group. Morales and Ramis have…
Optimization & Numerical Analysis seminar – “Krylov subspace methods for the solution of linear systems”” – Francesco Romani – Dipartimento di Informatica – Università di Pisa (Il seminario si svolgerà nella Sala Seminari Ovest al Dipartimento di Informatica)
Krylov subspace methods are iterative methods for the solution of linear systems which operate by multiplying the system matrix (sometimes also its transpose) by a vector. They are recommended when the system matrix is large and sparse or with a…
Normal forms and embedding problem for some formal transseries – Jean-Philippe Rolin (Université de Bourgogne)
Consider a hyperbolic polycycle of an analytic vector field in the real plane. The asymptotic expansion of its first return map is a series whose monomials are products of real powers of the variable and integer powers of its logarithm. Inspired by…