Dimension pure globale des anneaux commutatifs

For every (n,m) ? IN^?× IN ^?, verifying l We study direct systems of rings and give a bound for the pure - global - dimension of their limits, not depending on the ring cardinality. Using this result and a theorem of C0UCH0T we give examples of pure -heriditary group- rings (ie. of pure -global - dimension one) of large cardinality.

Finaly we prove - using a result of VASC0NCEL0S and a theorem of JENSEN - that some countably products of noetherian rings are coherent rings and that their pure - global - dimension is exactly two.     

Extensions hexaphiques des corps non commutatifs

A new class of extensions of skew fields, the so-called «hexaphic extensions», is studied in this paper. This study follows up «Anneaux polynômiaux à deux variables» [3] and «Anneaux hexaphiques d'une variable» [4]. A sub-class of hexaphic extensions is formed by pseudo-linear extensions. The general quadratic extensions are pseudo-linear [1]. General finite pseudo-linear extensions are now known [2]. In this paper, the hexaphic nature of general cubic extensions is shown and general finite hexaphic extensions are studied.     

Cohomologie des groupes et corps d'invariants multiplicatifs tordus

We give a cohomological calculation of the unramified Brauer group of a field of invariants under a twisted multiplicative action of a finite group. Received: October 13, 1992; final version: July 3, 1996     

Hauteurs de sous-espaces sur les corps non commutatifs

We study heights of subspaces of D ^N where D is a finite-dimensional rational division algebra and N a positive integer. We define them in terms of volumes of Euclidean lattices by extending a formula of W. Schmidt so that we recover the classical height if D is commutative. We review basic properties, prove a Siegel Lemma over D, a duality theorem and a new formula for the degree of certain abelian varieties. We further give matrix versions and compare our notion with the height defined through algebraic groups by J. Franke, Y. Manin and Y. Tschinkel.      

Sommes d'exponentielles à coefficients multiplicatifs et entiers sans grand facteur premier

Sans résumé     

Systèmes dynamiques non commutatifs et moyennabilité

Sans résumé     

Sur la classification des systèmes dynamiques non commutatifs

The purpose of this paper is to extend certain results on commutative dynamical systems and on von Neumann algebras (provided with their inner automorphism groups) to general dynamical systems: “decompositions” into finite, semifinite, properly infinite, purely infinite, discrete and continuous systems; induced systems, system extensions, properties of invariant weights, etc.     

Représentations Unitaires Continues d'Algèbres de Jordan et Fonctionnelles Positives

Summary This paper is concerned with the unitary continuous representations of Jordan Algebras.Positive functionals are defined for their application in Quantum Mechanics for states defining.     

Calcul fonctionnel et fonctions carrées dans les espaces Lp non commutatifs

We introduce suitable square functions for sectorial operators on noncommutative L^p-spaces, and we investigate their relationships with H^∞ functional calculus. To cite this article: M. Junge et al., C. R. Acad. Sci. Paris, Ser. I 337 (2003).     

Vecteurs de Witt non commutatifs et représentabilité de l'homologie modulop

Sans résuméOblatum 9-IV-1991 & 30-IX-1991Avec le soutien de la NSF et de la Fondation SloanURA 212 et UA D.0169 du CNRSURA 212 du CNRS     

Principe d'Oka,K-théorie et systèmes dynamiques non commutatifs

Sans résuméOblatum 16-X-1989     

Sur les ordres commutatifs avec un nombre fini de réseaux indécomposables

Sans résumé This revised version was published online in November 2006 with corrections to the Cover Date.