Factorisation de certains morphismes birationnels
Factorization of point configurations, cyclic covers, and conformal blocks
We describe a relation between the invariants of ordered points in projective -space and of points contained in a union of two linear subspaces. This yields an attaching map for GIT quotients parameterizing point configurations in these spaces, and we show that it respects the Segre product of the natural GIT polarizations. Associated to a configuration supported on a rational normal curve is a cyclic cover, and we show that if the branch points are weighted by the GIT linearization and the rational...
Faisceaux caractères
Faisceaux triangulaires sur l'espace projectif
Families of -divisible groups with constant Newton polygon.
Families of supersingular abelian surfaces
Filling boundaries of coarse manifolds in semisimple and solvable arithmetic groups
We provide partial results towards a conjectural generalization of a theorem of Lubotzky-Mozes-Raghunathan for arithmetic groups (over number fields or function fields) that implies, in low dimensions, both polynomial isoperimetric inequalities and finiteness properties. As a tool in our proof, we establish polynomial isoperimetric inequalities and finiteness properties for certain solvable groups that appear as subgroups of parabolic groups in semisimple groups, thus generalizing a theorem of Bux....
Filtration Patterns for Representations of Algebraic Groups and Their Frobenius Kernels.
Filtrations of cohomology modules for Chevalley groups
Filtrations of meromorphic C* actions on complex manifolds.
Filtrations of Principal Indecomposable Modules of Frobenius Kernels of Reductive Groups.
Finite group actions and étale cohomology
Finite group schemes, local moduli for abelian varieties, and lifting problems
Finite groups of automorphisms of K3 surfaces and the Mathieu group.
Finite locally free group schemes in characteristic p and Dieudonné modules.
Finiteness of local fundamental groups for quotients of affine varieties under reductive groups.
Finiteness Results for Algebraic K3 Surfaces.
Finite-order algebraic automorphisms of affine varieties.
Fixed points, exceptional orbits, and homology of affine -surfaces
Fixed points for reductive group actions on acyclic varieties
Let be a smooth, affine complex variety, which, considered as a complex manifold, has the singular -cohomology of a point. Suppose that is a complex algebraic group acting algebraically on . Our main results are the following: if is semi-simple, then the generic fiber of the quotient map contains a dense orbit. If is connected and reductive, then the action has fixed points if .