Parabolic exhaustions and analytic coverings.
Pinceaux linéaires de feuilletages sur CP(3) et conjecture de Brunella.
The general element of a pencil of Cod 1 foliation in CP(3) either has an invariant surface or contains a subfoliation by algebraic curves.
Positivity, vanishing theorems and rigidity of Codimension one Holomorphic Foliations
It is a known fact that the space of codimension one holomorphic foliations with singularities with a given ‘normal bundle’ has a natural structure of an algebraic variety. The aim of this paper is to consider the problem of the description of its irreducible components. To do this, we are interested in the problem of the existence of an integral factor of a twisted integrable differential 1–form defined on a projective manifold. We are going to do a geometrical analysis of the codimension one foliation...
Projective varieties invariant by one-dimensional foliations.
Quasialgebraic functions
We introduce and discuss a new class of (multivalued analytic) transcendental functions which still share with algebraic functions the property that the number of their isolated zeros can be explicitly counted. On the other hand, this class is sufficiently rich to include all periods (integral of rational forms over algebraic cycles).
Réalisation de germes de feuilletages holomorphes par des champs semi-complets en dimension 2
Reduction of the singularities of foliations and applications
Regular foliations along curves
Residue formulas for meromorphic functions on surfaces
Réversibilité et classification des centres nilpotents
Nous considérons un germe de 1-forme analytique dans dont le 1-jet est . Nous montrons que si l’équation définit un centre (i.e toutes les courbes solutions sont des cycles) il existe une involution analytique de préservant le portrait de phase du système. Géométriquement ceci signifie que les centres analytiques nilpotents sont obtenus par image réciproque par des applications pli. Un théorème de conjugaison équivariante permet d’obtenir une classification complète de ces centres.
Rigid meromorphic foliations on complex surfaces
Rigidité générique des feuilletages singuliers
Semicompleteness of homogeneous quadratic vector fields
We investigate the quadratic homogeneous holomorphic vector fields on that are semicomplete, this is, those whose solutions are single-valued in their maximal definition domain. To a generic quadratic vector field we rationally associate some complex numbers that turn out to be integers in the semicomplete case, thus showing that the linear equivalence classes of semicomplete vector fields are contained in some sort of lattice in the space of linear equivalence classes of quadratic ones. We prove...
Singular complete integrability
Singular foliations and differential -forms
Singular foliations of toric type
Singular Levi-flat hypersurfaces and codimension one foliations
We study Levi-flat real analytic hypersurfaces with singularities. We prove that the Levi foliation on the regular part of the hypersurface can be holomorphically extended, in a suitable sense, to neighbourhoods of singular points.
Singular sets of holonomy maps for algebraic foliations
In this article we investigate the natural domain of definition of a holonomy map associated to a singular holomorphic foliation of the complex projective plane. We prove that germs of holonomy between algebraic curves can have large sets of singularities for the analytic continuation. In the Riccati context we provide examples with natural boundary and maximal sets of singularities. In the generic case we provide examples having at least a Cantor set of singularities and even a nonempty open set...
Singularités des flots holomorphes. II
Singularités des flots holomorphes. II
Dans un article précédent [Singularité des flots holomorphes, Ann. Inst. Fourier, Grenoble, 46-2 (1996), 411-428], le deuxième auteur démontrait, en particulier, qu’un champ de vecteurs holomorphe complet sur une surface complexe ne peut posséder une singularité isolée dont le deuxième jet est nul. Nous nous proposons ici de donner une description précise des champs de vecteurs holomorphes complets sur les surfaces complexes qui possèdent une singularité isolée dont le premier jet est nul. Dans...