Algebraic -theory and etale cohomology
Applications of weight-two motivic cohomology.
Crystalline conjecture via -theory
Differential Equations associated to Families of Algebraic Cycles
We develop a theory of differential equations associated to families of algebraic cycles in higher Chow groups (i.e., motivic cohomology groups). This formalism is related to inhomogenous Picard–Fuchs type differential equations. For a families of K3 surfaces the corresponding non–linear ODE turns out to be similar to Chazy’s equation.
Elliptic operators and higher signatures
Building on the theory of elliptic operators, we give a unified treatment of the following topics: - the problem of homotopy invariance of Novikov’s higher signatures on closed manifolds, - the problem of cut-and-paste invariance of Novikov’s higher signatures on closed manifolds, - the problem of defining higher signatures on manifolds with boundary and proving their homotopy invariance.
Gersten's conjecture for some complexes of vanishing cycles.
Hochschild cohomology of complex spaces and Noetherian schemes.
Homologie du groupe linéaire et polylogarithmes
Karoubi’s relative Chern character and Beilinson’s regulator
We construct a variant of Karoubi’s relative Chern character for smooth varieties over and prove a comparison result with Beilinson’s regulator with values in Deligne-Beilinson cohomology. As a corollary we obtain a new proof of Burgos’ Theorem that for number fields Borel’s regulator is twice Beilinson’s regulator.
La conjecture de Milnor
Motivic complexes of Suslin and Voevodsky
Motivic functors.
On the cyclic homology of ringed spaces and schemes.
Pour une théorie inconditionnelle des motifs
Proof of Nadel’s conjecture and direct image for relative -theory
A “relative” -theory group for holomorphic or algebraic vector bundles on a compact or quasiprojective complex manifold is constructed, and Chern-Simons type characteristic classes are defined on this group in the spirit of Nadel. In the projective case, their coincidence with the Abel-Jacobi image of the Chern classes of the bundles is proved. Some applications to families of holomorphic bundles are given and two Riemann-Roch type theorems are proved for these classes.
Propriétés du groupe tannakien des structures de Hodge -adiques et torseur entre cohomologies cristalline et étale
On donne des propriétés de la catégorie tannakienne des modules de Dieudonné filtrés sur un corps -adique (ces modules de Dieudonné jouent en -adique un rôle analogue aux structures de Hodge complexes). On prouve l’existence d’un foncteur fibre sur et la simple connexité du groupe associé. Ceci permet de montrer, sous la conjecture de Fontaine : “faiblement admissible entraîne admissible”, une conjecture de Rapoport et Zink décrivant le torseur entre cohomologie cristalline et étale, et de prouver...
Rigidity II: non-orientable case.
The Grothendieck-Riemann-Roch theorem for group scheme actions
Topologie log-syntomique, cohomologie log-cristalline et cohomologie de Čech
Une remarque sur la cohomologie du faisceau de Zariski de la K-théorie de Milnor sur une variété lisse complexe.