Stabilisation, bordism and embedded spheres in 4-manifolds.
Stability Results for Topological Spaces.
Stable cohomotopy groups of compact spaces
We show that one can reduce the study of global (in particular cohomological) properties of a compact Hausdorff space X to the study of its stable cohomotopy groups . Any cohomology functor on the homotopy category of compact spaces factorizes via the stable shape category ShStab. This is the main reason why the language and technique of stable shape theory can be used to describe and analyze the global structure of compact spaces. For a given Hausdorff compact space X, there exists a metric compact...
Stable Equivariant Bordism.
Stable rational cohomology of automorphism groups of free groups and the integral cohomology of moduli spaces of graphs.
It is not known whether or not the stable rational cohomology groups H*(Aut(F∞);Q) always vanish (see Hatcher in [5] and Hatcher and Vogtmann in [7] where they pose the question and show that it does vanish in the first 6 dimensions). We show that either the rational cohomology does not vanish in certain dimensions, or the integral cohomology of a moduli space of pointed graphs does not stabilize in certain other dimensions. Similar results are stated for groups of outer automorphisms. This yields...
Stable Vector Bundles over the Projective Orthogonal Groups.
Stably spherical classes in the K-homology of a finite group.
State-sum invariants of knotted curves and surfaces from quandle cohomology.
Steenrod homology
Strong surjectivity of mappings of some 3-complexes into 3-manifolds
Let K be a CW-complex of dimension 3 such that H³(K;ℤ) = 0, and M a closed manifold of dimension 3 with a base point a ∈ M. We study the problem of existence of a map f: K → M which is strongly surjective, i.e. such that MR[f,a] ≠ 0. In particular if M = S¹ × S² we show that there is no f: K → S¹ × S² which is strongly surjective. On the other hand, for M the non-orientable S¹-bundle over S² there exists a complex K and f: K → M such that MR[f,a] ≠ 0.
Strong surjectivity of mappings of some 3-complexes into
Let K be a CW-complex of dimension 3 such that H 3(K;ℤ) = 0 and the orbit space of the 3-sphere with respect to the action of the quaternion group Q 8 determined by the inclusion Q 8 ⊆ . Given a point a ∈ , we show that there is no map f:K → which is strongly surjective, i.e., such that MR[f,a]=min(g −1(a))|g ∈ [f] ≠ 0.
Structural Theorems for Topological Actions of Z...-Tori on Real, Complex and Quarternionic Projective Spaces
Subdivisiones Relativas Sobre Pre-Haces Y Homologias Simpliciales Isomorfas.
Successive homology operations and their applications
Sui teoremi di De Rham
Sur la cohomologie feuilletée
Sur la cohomologie réelle des groupes de Lie simples réels
Sur la complétion de la -théorie équivariante
Sur la dualité de Poincaré.
Sur la topologie de l'espace des systèmes linéaires hamiltoniens anti symétriques accessibles
Dans cet article nous donnons les formes normales des sytèmes linéaires hamiltoniens antisymétriques accessibles . Nous construisons une stratification et une décomposition cellulaire analytique de , puis nous prouvons que son groupe d’homotopie est isomorphe à celui d’une grassmanienne. Ensuite, nous démontrons que est homotopiquement équivalent à l’espace des systèmes linéaires accessibles. En appliquant ces résultats topologiques, on peut prouver qu’il n’existe pas de paramétrisation continue...