Prescription de la courbure de Ricci au voisinage de la métrique hyperbolique

On the unit ball of, one considers the standard hyperbolic metric H₀ whose Ricci curvature equals R₀ and Riemann-Christoffel curvature is. We prove that, for any symmetric tensor R near R₀, there exists a unique metric H near H₀ whose Ricci curvature is R. We deduce in the C^∞ case that the image of the Riemann-Christoffel operator is a submanifold in a neighborhood of. Finally, we study more precisely the Ricci equation in dimension 2.     

Quantification de la dualité de Grassmann

Let V be a complex vector space of dimension n, %plane1D;53E; (resp. %plane1D;53E;^*) the Grassmann manifold of p-dimensional (resp. (n — p)-dimensional) subspaces of V, and of Ω the relation of transversality in %plane1D;53E;*%plane1D;53E;^*. We announced in [6] equivalences between derived categories of sheaves and of D-modules on %plane1D;53E; and %plane1D;53E; defined by the integral transforms associated to Ω. We show here that these transforms exchange the D-modules associated to the holomorphic line bundles on %plane1D;53E; and %plane1D;53E;^*. This is equivalent to “quantizing” the underlying contact transformation between certain open dense subsets of the cotangent bundles. In the case p = 1, we recover already known results for the projective duality (see [1] and [5]).     

Une variante de la méthode de majoration de Cauchy

Sans résumé Conférence faite au Congrès des mathématiciens scandinaves à Copenhague en ao?t 1964. 10-652932     

Sur la convergence de certaines intégrales de la théorie du potentiel

Sans résuméEn hommage au professeurOstrowski     

Extensions de fonctions d'un voisinage de la sphère à la boule

In this note, we are interested in the problem of extending a germ defined along the standard sphere and whose restriction to the sphere is Morse to a function F defined on the ball bounded by the sphere, without critical point. We give an algebraic necessary condition dealing with the Morse complexes of f with $\mathbb{Z}$ coefficients.     

Une q-déformation de la transformation de Bargmann vraie-polyanalytique

We introduce a q-analog of the true-polyanalytic Bargmann transform on $\mathbb{C}$.     

A propos de la propriété de Bergman

In a recent preprint, George M. Bergman has investigated the following property:for any generating set X of the group G there exists an integer n such that any element of G is a product of n elements of $\text{X}\cup {\text{X}}^{\mathrm{?1}}$. We will say in this case that G has the Bergman property.We have solved some of the questions asked in the above mentioned preprint and have found it suitable to investigate this property in a more general context, in particular for rings (essentially Boolean rings). To cite this article: A. Khelif, C. R. Acad. Sci. Paris, Ser. I 342 (2006).     

Une approche nouvelle de la dualité locale de Tate

Sans résumé Received July 11, 1999 / Accepted September 25, 2000 / Published online February 5, 2001     

Généralisation de la notion de l'enveloppe

Sans résumé Présenté par G. Hajós     

Sur la caractérisation de certaines classes de fonctions au sens de la théorie constructive des fonctions

Sans résumé     

Sur la torsion de la distribution ordinaire universelle attachée à un corps de nombres

We study the torsion subgroup of the universal ordinary distribution related to a general number field. We describe a way to control this subgroup. We apply this method to the special case of an imaginary quadratic field, and we give examples of such fields where these torsion subgroups are non-trivial. Received: 4 January 2001 / Revised version: 17 May 2001     

Sur la répartition des valeurs de la fonction d'Euler

Let (x) denote the number of those integers n with (n) x, where denotes the Euler function. Improving on a well-known estimate of Bateman (1972), we show that (x)-Ax R(x), where A=(2)(3)/(6) and R(x) is essentially of the size of the best available estimate for the remainder term in the prime number theorem.     

L'influence de la géométrie de Bolyai-Lobatchevsky sur le développement de la méthode axiomatique

Sans résumé     

Sur la fonction sommatoire de la fonction de von Mangoldt généralisée

We give an identity for the summatory function of the generalized von Mangoldt function Received: 19 February 2007