Bass numbers and Golod rings.
Cochain operations and subspace arrangements.
Cohomologie, -groupes et fonctorialité
Cohomology theories and infinite CW-Complexes.
Comparison of spectral sequences involving bifunctors.
Deformations and derived categories
In this paper we generalize the deformation theory of representations of a profinite group developed by Schlessinger and Mazur to deformations of objects of the derived category of bounded complexes of pseudocompact modules for such a group. We show that such objects have versal deformations under certain natural conditions, and we find a sufficient condition for these versal deformations to be universal. Moreover, we consider applications to deforming Galois cohomology classes and the étale hypercohomology...
Derived de Rham Complex and Cyclic Homology.
Duality and the DeRham Cohomology of Infinitesimal Neighborhoods.
Group extensions, crossed pairs and an eight term exact sequence.
Homotopie des foncteurs en groupes.
Homotopy decompositions of orbit spaces and the Webb conjecture
Let p be a prime number. We prove that if G is a compact Lie group with a non-trivial p-subgroup, then the orbit space of the classifying space of the category associated to the G-poset of all non-trivial elementary abelian p-subgroups of G is contractible. This gives, for every G-CW-complex X each of whose isotropy groups contains a non-trivial p-subgroup, a decomposition of X/G as a homotopy colimit of the functor defined over the poset , where sd is the barycentric subdivision. We also...
Introduction to -infinity algebras and modules.
Lower central series, augmentation quotients and homology of groups.
Modules with injective cohomology, and local duality for a finite group.
Motivically functorial coniveau spectral sequences; direct summands of cohomology of function fields.
Nondegenerate cohomology pairing for transitive Lie algebroids, characterization
The Evens-Lu-Weinstein representation (Q A, D) for a Lie algebroid A on a manifold M is studied in the transitive case. To consider at the same time non-oriented manifolds as well, this representation is slightly modified to (Q Aor, Dor) by tensoring by orientation flat line bundle, Q Aor=QA⊗or (M) and D or=D⊗∂Aor. It is shown that the induced cohomology pairing is nondegenerate and that the representation (Q Aor, Dor) is the unique (up to isomorphy) line representation for which the top group of...
Obstructions for deformations of complexes
We develop two approaches to obstruction theory for deformations of derived isomorphism classes of complexes of modules for a profinite group over a complete local Noetherian ring of positive residue characteristic.
On Central Group Extensions and Homology
On Convergence of Spectral Sequences.
On distributive homological algebra, I. RE-categories