October 29, 2014 
13:15  15:00 
Severine Rigot (Nice) 

"Covering lemmas in the Heisenberg groups"
Abstract: In this talk I will explain the main ideas underlying the construction of a homogeneous distance on the Heisenberg groups for which the Besicovitch covering property (BCP) holds (joint work with E. Le Donne). This covering property is known to be an important tool, being for instance equivalent to the validity of the theorem of differentiation for any Radon measure. To put this result in perspective I will also give criteria implying the nonvalidity of BCP, showing that in some sense our construction is sharp.


Auditorium 1.309, Sciences de la Terre building

November 4, 2014 
15:15  17:00 
Andrea Schioppa (ETHZ) 

"Vector fields on metric mesure spaces, and 1rectifiable structure"
Abstract: In this talk I will describe a general approach to
differentiaton of realvalued Lipschitz functions defined on metric
measure spaces. As an application, I will discuss a quantitative
characterization of differentiability spaces in the sense of Cheeger
and Keith.


Auditorium 2.73, Physics building

November 11, 2014 
15:15  17:00 
Davide Vittone (Univ. di Padova) 

"Minimizers of the area functional in the Heisenberg group"
Abstract: We consider the area functional for graphs in the
subRiemannian Heisenberg group and study minimizers of the associated
Dirichlet problem. We prove that, under a bounded slope condition on
the boundary datum, there exists a unique minimizer and that this
minimizer is Lipschitz continuous. We also provide an example showing
that, in the first Heisenberg group, Lipschitz regularity cannot be
improved even under the bounded slope condition. This is based on a
joint work with A. Pinamonti, F. Serra Cassano and G. Treu. 

Auditorium 2.73, Physics building

April 23, 2015 
15:15  17:00 
Kai Rajala (Univ. Jyvaskyla) 

"Uniformization of metric surfaces"
Abstract: We discuss a generalization of the classical uniformization theorem to metric spaces that have locally finite Hausdorff 2measure. Namely, we give a necessary and sufficient condition for such spaces to be quasiconformally equivalent to a euclidean space. We also discuss connections to quasisymmetric parametrization problems.


Auditorium 2.52, Physics building
