Crystallizations of generalized Neuwirth manifolds.
Cubical approximation and computation of homology
The purpose of this article is to introduce a method for computing the homology groups of cellular complexes composed of cubes. We will pay attention to issues of storage and efficiency in performing computations on large complexes which will be required in applications to the computation of the Conley index. The algorithm used in the homology computations is based on a local reduction procedure, and we give a subquadratic estimate of its computational complexity. This estimate is rigorous in two...
Cubulations, immersions, mappability and a problem of Habegger
Curiosités Lagrangiennes en dimension 4
Dans ce texte, on définit, pour les immersions lagrangiennes de variétés fermées dans , une notion d’aire symplectique enlacée. Puis on construit, dans le cas , un certain nombre de surfaces lagrangiennes enlaçant une aire infinie. Dans le cas des surfaces exactes, elles ont le minimum de points doubles possible permis par la théorie (sauf la sphère), c’est-à-dire moins que prévu par quelques conjectures.
Curvature of lift spaces
Curvature, tangentiality, and controlled topology.
Curvature testing in 3-dimensional metric polyhedral complexes.
Curves and surfaces in real projective spaces: an approach to generic projections
Cusp structures of alternating links.
Cut loci of closed surfaces without conjugate points
Cutting and Pasting of Involutions and Fiberings over the Circle within a Bordism Class.
Cycle exceptionnel de l'éclatement de Nash d'une hypersurface analytique complexe à singularité isolée
Cycles for the Dynamical Study of Foliated Manifolds and Complex Manifolds.
Cycles on algebraic models of smooth manifolds
Every compact smooth manifold is diffeomorphic to a nonsingular real algebraic set, called an algebraic model of . We study modulo 2 homology classes represented by algebraic subsets of , as runs through the class of all algebraic models of . Our main result concerns the case where is a spin manifold.
Cyclic actions on - and -bundles over
Cyclic branched coverings and homology 3-spheres with large group actions
We show that, if the covering involution of a 3-manifold M occurring as the 2-fold branched covering of a knot in the 3-sphere is contained in a finite nonabelian simple group G of diffeomorphisms of M, then M is a homology 3-sphere and G isomorphic to the alternating or dodecahedral group 𝔸₅ ≅ PSL(2,5). An example of such a 3-manifold is the spherical Poincaré sphere. We construct hyperbolic analogues of the Poincaré sphere. We also give examples of hyperbolic ℤ₂-homology 3-spheres with PSL(2,q)-actions,...
Cyclic branched coverings of 2-bridge knots.
In this paper we study the connections between cyclic presentations of groups and the fundamental group of cyclic branched coverings of 2-bridge knots. Then we show that the topology of these manifolds (and knots) arises, in a natural way, from the algebraic properties of such presentations.
Cyclic branched coverings of knots and homology spheres.
We study cyclic coverings of S3 branched over a knot, and study conditions under which the covering is a homology sphere. We show that the sequence of orders of the first homology groups for a given knot is either periodic of tends to infinity with the order of the covering, a result recently obtained independently by Riley. From our computations it follows that, if surgery on a knot k with less than 10 crossings produces a manifold with cyclic fundamental group, then k is a torus knot.
Cyclic Crystallizations of Spheres.
Cyclic group actions on odd-dimensional spheres.