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Levi-flat filling of real two-spheres in symplectic manifolds (II)

Hervé Gaussier, Alexandre Sukhov (2012)

Annales de la faculté des sciences de Toulouse Mathématiques

We consider a compact almost complex manifold ( M , J , ω ) with smooth Levi convex boundary M and a symplectic tame form ω . Suppose that S 2 is a real two-sphere, containing complex elliptic and hyperbolic points and generically embedded into M . We prove a result on filling S 2 by holomorphic discs.

Levi-flat invariant sets of holomorphic symplectic mappings

Xianghong Gong (2001)

Annales de l’institut Fourier

We classify four families of Levi-flat sets which are defined by quadratic polynomials and invariant under certain linear holomorphic symplectic maps. The normalization of Levi- flat real analytic sets is studied through the technique of Segre varieties. The main purpose of this paper is to apply the Levi-flat sets to the study of convergence of Birkhoff's normalization for holomorphic symplectic maps. We also establish some relationships between Levi-flat invariant sets...

Levi's forms of higher codimensional submanifolds

Andrea D'Agnolo, Giuseppe Zampieri (1991)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

Let X C n , let M be a C 2 hypersurface of X , S be a C 2 submanifold of M . Denote by L M the Levi form of M at z 0 S . In a previous paper [3] two numbers s ± S , p , p T ˙ S * X z 0 are defined; for S = M they are the numbers of positive and negative eigenvalues for L M . For S M , p S × M T ˙ * S X ) , we show here that s ± S , p are still the numbers of positive and negative eigenvalues for L M when restricted to T z 0 C S . Applications to the concentration in degree for microfunctions at the boundary are given.

Lie group structures and reproducing kernels on the unit ball of n

Umberto Sampieri (1984)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

Si introducono due strutture di gruppo di Lie su un dominio di Siegel omogeneo di n . Per la palla unitaria si definisce una famiglia ad un parametro di strutture intermedie; ad ognuna di esse viene associato naturalmente un nucleo riproducente ottenendo un'interpolazione tra il nucleo di Bergman ed il nucleo di Szego.

Lie group structures on groups of diffeomorphisms and applications to CR manifolds

M. Salah Baouendi, Linda Preiss Rothschild, Jörg Winkelmann, Dimitri Zaitsev (2004)

Annales de l’institut Fourier

We give general sufficient conditions to guarantee that a given subgroup of the group of diffeomorphisms of a smooth or real-analytic manifold has a compatible Lie group structure. These results, together with recent work concerning jet parametrization and complete systems for CR automorphisms, are then applied to determine when the global CR automorphism group of a CR manifold is a Lie group in an appropriate topology.

Lieu discriminant d’un germe analytique de corang 1 de , 0 2 vers , 0 2

Philippe Maisonobe (1982)

Annales de l'institut Fourier

On considère des germes d’applications analytiques de C , 0 2 vers C , 0 2 , de corang 1, finis, à lieu critique irréductible. De corang 1 signifie qu’il s’écrit après un bon choix de coordonnées locales sous la forme: ( x , u ) ( x , P ( x , u ) ) P u ' ( 0 , 0 ) = 0 . On donne des conditions nécessaires et suffisantes pour qu’une courbe plane irréductible soit le lieu discriminant d’un tel germe d’applications : ce sont des conditions numériques portant sur les exposants de Puiseux. Ce problème est lié à celui de la représentation d’une variété lagrangienne...

Limit currents and value distribution of holomorphic maps

Daniel Burns, Nessim Sibony (2012)

Annales de l’institut Fourier

We construct d -closed and d d c -closed positive currents associated to a holomorphic map φ via cluster points of normalized weighted truncated image currents. They are constructed using analogues of the Ahlfors length-area inequality in higher dimensions. Such classes of currents are also referred to as Ahlfors currents. We give some applications to equidistribution problems in value distribution theory.

Limit trees and generic discriminants of minimal surface singularities

Eric Akéké (2008)

Annales de la faculté des sciences de Toulouse Mathématiques

According to R. Bondil the dual graph of the minimal resolution of a minimal normal surface singularity determines the generic discriminant of that singularity. In this article we give with combinatorial arguments the link between the limit trees and the generic discriminants of minimal normal surface singularities. The weighted limit trees of a minimal surface singularity determine the generic discriminant of that singularity.

Line bundles with partially vanishing cohomology

Burt Totaro (2013)

Journal of the European Mathematical Society

Define a line bundle L on a projective variety to be q -ample, for a natural number q , if tensoring with high powers of L kills coherent sheaf cohomology above dimension q . Thus 0-ampleness is the usual notion of ampleness. We show that q -ampleness of a line bundle on a projective variety in characteristic zero is equivalent to the vanishing of an explicit finite list of cohomology groups. It follows that q -ampleness is a Zariski open condition, which is not clear from the definition.

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