Le graphe d'un feuilletage admettant un système transverse d'équations differentielles.
Le groupe d'automorphismes du groupe modulaire
Le but de cet article est de donner une autre démonstration plus simple du théorème d’Ivanov (Théorème 1) qui assure que le groupe de toutes les difféotopies d’une surface orientable et fermée de genre est complet. En étudiant l’action d’un automorphisme quelconque du groupe sur les difféotopies d’ordre fini, on montre que les involutions hyperelliptiques sont globalement préservées. Le théorème d’Ivanov est alors une conséquence d’un résultat de Dyer et Grossmann qui affirm que le groupe...
Le problème de la finitude du nombre de cycles limites
Le problème d'équivalence pour les pseudogroupes de Lie : méthodes intrinsèques
Le théorème de -cobordisme
Le type d'homotopie du groupe des difféomorphismes d'une surface compacte
Leafwise hyperbolicity; a correction.
Leafwise hyperbolicity of proper foliations.
Leaves of foliations with a transverse geometric structure of finite type.
In this short note we find some conditions which ensure that a G foliation of finite type with all leaves compact is a Riemannian foliation of equivalently the space of leaves of such a foliation is a Satake manifold. A particular attention is paid to transversaly affine foliations. We present several conditions which ensure completeness of such foliations.
Leaves of Markov local minimal sets in foliations of codimension one.
The authors continue their study of exceptional local minimal sets with holonomy modeled on symbolic dynamics (called Markov LMS [C-C 1]). Here, an unpublished theorem of G. Duminy, on the topology of semiproper exceptional leaves, is extended to every leaf, semiproper or not, of a Markov LMS. Other topological results on these leaves are also obtained.
Lefschetz fibrations, complex structures and Seifert fibrations on .
Lefschetz fibrations on compact Stein surfaces.
Lefschetz pencils and divisors in moduli space.
Lefschetz theorems for the integral leaves of a holomorphic one-form
Legendrian and transverse twist knots
In 1997, Chekanov gave the first example of a Legendrian nonsimple knot type: the knot. Epstein, Fuchs, and Meyer extended his result by showing that there are at least different Legendrian representatives with maximal Thurston-Bennequin number of the twist knot with crossing number . In this paper we give a complete classification of Legendrian and transverse representatives of twist knots. In particular, we show that has exactly Legendrian representatives with maximal Thurston–Bennequin...
Legendrian dual surfaces in hyperbolic 3-space
We consider surfaces in hyperbolic 3-space and their duals. We study flat dual surfaces in hyperbolic 3-space by using extended Legendrian dualities between pseudo-hyperspheres in Lorentz-Minkowski 4-space. We define the flatness of a surface in hyperbolic 3-space by the degeneracy of its dual, which is similar to the case of the Gauss map of a surface in Euclidean 3-space. Such surfaces are a kind of ruled surfaces. Moreover, we investigate the singularities of these surfaces and the dualities...
Legendrian foliations on almost -manifolds.
Legendrian graphs and quasipositive diagrams
In this paper we clarify the relationship between ribbon surfaces of Legendrian graphs and quasipositive diagrams by using certain fence diagrams. As an application, we give an alternative proof of a theorem concerning a relationship between quasipositive fiber surfaces and contact structures on . We also answer a question of L. Rudolph concerning moves of quasipositive diagrams.
Legendrian knots and monopoles.
Leibniz cohomology for differentiable manifolds
We propose a definition of Leibniz cohomology, , for differentiable manifolds. Then becomes a non-commutative version of Gelfand-Fuks cohomology. The calculations of reduce to those of formal vector fields, and can be identified with certain invariants of foliations.