In a pioneering 1981 paper De Concini and Procesi provided a beautiful description for cohomology of fixed point sets (Springer fibers) (G/B)_ϵ in type A. This was an important precursor to two later...
We consider the question of determining reductive overgroups of regular unipotent elements
in simple algebraic groups and in particular give a condition which guarantees that the
overgroup does not li...
Kodaira and Kawamata-Viehweg vanishing is frequently used to lift sections of adjoint
bundles, a crucial part of many arguments in the classification theory of algebraic varieties,
notably in many pro...
Finite flat group schemes are important in number theory.
We explain what we do and don't know about their structure over rings of integers of number
fields, in particular over Z.
This is joint work w...
I will discuss geometric and dynamical properties of actions of discrete groups on Riemannian symmetric spaces. I will highlight some aspects of the interplay between geometry and dynamics, and presen...
We will report on a joint work with J. Cao. Our main result establishes the extension of twisted canonical forms defined on an infinitesimal neighborhood of the central fiber of a Kahler family under ...
The canonical line bundle and the corresponding canonical sheaf belong to the most
important geometric/analytic objects associated to a complex manifold. They play a crucial
role e.g. in classificatio...
The description of regular blocks of the category O of a complex semisimple Lie algebra in
terms of perverse sheaves on a flag variety has been a crucial tool for its study, and in
particular for the ...
Campana introduced the class of special varieties as the varieties admitting no maps onto
an orbifold of general type. They are also characterized by the non-existence of Bogomolov
sheaves which are r...
I will compare work of Formanek on a certain construction of central polynomials with that of Collins on integration on unitary groups. These two quite disjoint topics share the construction of the sa...
We make a universal construction of Bruhat-Tits group scheme on wonderful embeddings of adjoint groups in the absolute and relative settings of adjoint Kac-Moody groups. These group schemes have natur...
