Top-level heading

Racconti di carte e di numeri

 Il seminario è stato organizzato dalla Biblioteca di Matematica allo scopo di presentare il lavoro svolto dai due tirocinanti della Facoltà di Lettere e Culture Moderne, Irene Guerriero e France...

Canonical sheaves at isolated canonical singularities

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...

Overgroups of regular unipotent elements in simple algebraic groups

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...

Replacing vanishing theorems in mixed characteristic and the Minimal Model Program
for 3-folds over excellent schemes

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 over Z

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...

Numerically special varieties

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...

Perverse sheaves on affine flag varieties, geometry of the dual group, and
representations

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 ...

Higher rho numbers and metrics of positive scalar curvature

The analytic surgery sequence is a long exact sequence of K-theory groups which combines topological information (the K-homology of manifolds), index theoretic information (the K-theory of group C*-al...

On extension of twisted canonical forms defined on the central fiber of a Kähler family

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 ...