WorldCat Identities

Bekka, M. Bachir

Overview
Works: 15 works in 44 publications in 2 languages and 1,442 library holdings
Classifications: QA611.5, 515.42
Publication Timeline
Key
Publications about  M. Bachir Bekka Publications about M. Bachir Bekka
Publications by  M. Bachir Bekka Publications by M. Bachir Bekka
Most widely held works by M. Bachir Bekka
Ergodic theory and topological dynamics of group actions on homogeneous spaces by M. Bachir Bekka ( )
14 editions published in 2000 in English and held by 1,191 WorldCat member libraries worldwide
This book focuses on recent developments in the study of geodesic flows on homogenous spaces
Kazhdan's property (T) by M. Bachir Bekka ( Book )
14 editions published in 2008 in English and held by 232 WorldCat member libraries worldwide
A comprehensive introduction to the role of Property (T), with applications to an amazing number of fields within mathematics
Phénomènes de rigidité pour un réseau dans un produit de groupes by Nicolas Louvet ( Book )
2 editions published between 1998 and 2009 in French and held by 3 WorldCat member libraries worldwide
Une classe remarquable de groupes localement compacts a été découverte par Kazhdan en 1967. Il s'agit des groupes possédant la propriété (t)(appelés aussi groupes de Kazhdan). Ces groupes jouissent d'innombrables propriétés de rigidité et ont des applications en géométrie, théorie des graphes, algèbre d'opérateurs, un groupe g localement compact possède la propriété (t) de Kazhdan si la représentation triviale de dimension un de g est un point isolé dans le dual unitaire de g. De façon équivalente, si le groupe g est dénombrable à l'infini alors g possède la propriété (t) si et seulement si le premier espace de cohomologie de g a coefficients dans une représentation unitaire quelconque est trivial. De plus, un réseau (i.e. un sous-groupe discret de covolume fini) dans un groupe de Kazhdan possède également la propriété (t). Dans ce travail, nous obtenons, pour un réseau irréductible dans le produit direct de deux groupes localement compacts, des résultats du type propriété (t) affaiblie : annulation du premier espace de cohomologie pour une famille de représentations ou isolation de la représentation triviale dans un sous ensemble naturel de représentations, ainsi que des résultats du type super-rigidité des représentations : telles représentations du réseau proviennent de restrictions de représentations du groupe ambiant. Nous donnons également quelques conséquences de ces résultats (absence de trace sur la c*-algèbre du réseau, rigidité des représentations de dimension finie) ainsi qu'une liste de groupes pour lesquels nos résultats s'appliquent
Some groups whose reduced C*-Algebra is simple by M. Bachir Bekka ( Book )
1 edition published in 1993 in English and held by 3 WorldCat member libraries worldwide
Conjecture des diviseurs de zéro et propriété (T) by Christian Masse ( )
2 editions published in 2004 in French and held by 2 WorldCat member libraries worldwide
This work behaves two independent parties : the first chapter draft of the zero divisor conjecture, in the framework of abelian groups, nilpotent groups, semi-simple groups and at last discrete groups. In the second chapter, we prove that the group Sp (n,1) has property (T) of Kazhdan of two different manners ; the first proof is based on ideas of M. Cowling and U. Haargerup, the second on ideas of B. Bekka, P. Harpe and A. Valette
Représentations unitaires des réseaux dans les groupes de Lie Nilpotents by Pierre Driutti ( )
2 editions published between 1999 and 2009 in French and held by 2 WorldCat member libraries worldwide
Le G be a real Nilpotent, connected and simply connected Lie group. If H is lattice in G, we study the restrictions of irreductible unitary representations of G to H, as well as the action (by mean of right translation) of subgroups of G on the nilmanifold H\G
Complemented *-primitive ideals in L 1 -algebras of exponential Lie groups and of motion groups by M. Bachir Bekka ( Book )
1 edition published in 1988 in English and held by 1 WorldCat member library worldwide
Frontières de Poisson d'opération quantiques et trajectoires quantiques by Bunrith Jacques Lim ( Book )
1 edition published in 2010 in French and held by 1 WorldCat member library worldwide
The study of this thesis takes place in mathematical foundations of quantum information theory and quantum physics, through the study of the set of fixed points of a quantum operation (also called Poisson boundary), and the study of quantum trajectories in infinite dimension. At first, we precise the Poisson boundary of a quantum operation. Then we answer negatively some conjectures appearing in the work of Arias et al. [Fixed points of quantum operations, J. Math. Phys. 43, 5872 (2002)] concerning Poisson boundaries of quantum operations. In second place, we identify the noncommutative Poisson boundary on a s-discrete measured groupoid. It enables us to give another proof of the amenability of the Poisson extension of the groupoid. At last, results concerning asymptotical purification of quantum trajectories taking values in a strongly compact algebra are obtained
Groups with simple reduced C*-algebras by Pierre de La Harpe ( Book )
1 edition published in 1999 in English and held by 1 WorldCat member library worldwide
Familles de graphes expanseurs et paires de Hecke by M. Bachir Bekka ( Book )
1 edition published in 2002 in English and held by 1 WorldCat member library worldwide
Dynamique des actions de semi-groupes d'endomorphismes sur des nilvariétés by Jean-Romain Heu ( Book )
1 edition published in 2010 in French and held by 1 WorldCat member library worldwide
The dynamical properties of automorphism groups acting on tori have been widely studied. Nilpotent real Lie groups are a first generalization of abelian real Lie groups. Their quotients by lattices are called nilmanifolds. They generalize the notion of torus. In this thesis, we study the action of groups and semigroups of endomorphisms of some nilmanifolds, such as Heisenberg nilmanifolds. We describe three dynamical aspects of these actions : the density of orbits, the set of invariant measures and the existence of a spectral gap for operators on the L²-spaces associated to the nilmanifolds
Groups with simple reduced C*-algebras by M. Bachir Bekka ( )
1 edition published in 2000 in English and held by 1 WorldCat member library worldwide
Irreducibility of unitary group representations and reproducing kernels Hilbert spaces by M. Bachir Bekka ( Book )
1 edition published in 2003 in English and held by 1 WorldCat member library worldwide
On Mackey's irreducibility criterion for induced representations by M. Bachir Bekka ( )
1 edition published in 2003 in English and held by 1 WorldCat member library worldwide
Rigidité et non-rigidité d'actions de groupes sur les espaces Lp non-commutatifs by Baptiste Olivier ( )
1 edition published in 2013 in English and held by 1 WorldCat member library worldwide
We studied rigidity properties and strong non-rigidity properties for group actions on non-commutative Lp spaces. Recently, variants of Kazhdan's property (T) and fixed-point property (FH) were introduced, respectively called property (TB) and property (FB), and described in terms of orthogonal representations on a Banach space B. We are interested in the case where B is a non-commutative Lp space Lp(M), associated to a von Neumann algebra M. In a first part, we show that if a group has property (T), then it has property (TLp(M)) for any von Neumann algebra M. We deduce that higher rank groups have property (FLp(M)). We show that for some algebras, such as M=B(H), properties (T) and (TLp(M)) are equivalent. By contrast, we characterize groups with property (Tlp), and show that this class of groups is larger than the one with property (T). In a second part, we introduce variants of the Haagerup property (H), namely properties (HLp(M)) and a-FLp(M)-menability, defined in terms of actions on the space Lp(M). We describe relationships between property (H) and its variant (HLp(M)) for different algebras M. We show that groups with property (H) are a-FLp(M)-menable for some algebras M, such as the hyperfinite II infinite factor
 
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Audience Level
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Audience level: 0.57 (from 0.00 for Rigidité ... to 0.82 for Kazhdan's ...)
Alternative Names
Bekka Bachir
Bekka, M. B.
Bekka, M. B. (M. Bachir)
Bekka, M. Bachir
Bekka, M. Bahir.
Bekka, Mohammed el Bachir.
Languages
English (36)
French (8)
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