Sobolev- und Sobolev-Hardy-Räume auf S1: Dualitätstheorie und Funktionalkalküle.
Sobre el espectro de derivaciones y automorfismos de las álgebras de Banach.
Sobre un álgebra de funciones casi analíticas.
Solution d'un problème d'Erdös, Gillman et Henriksen et application à l'étude des homomorphismes de C-(K).
Solved and unsolved problems in generalized notions of amenability for Banach algebras
We survey the recent investigations on approximate amenability/contractibility and pseudo-amenability/contractibility for Banach algebras. We will discuss the core problems concerning these notions and address the significance of any solutions to them to the development of the field. A few new results are also included.
Some algebraic and homological properties of Lipschitz algebras and their second duals
Let be a metric space and . We study homological properties and different types of amenability of Lipschitz algebras and their second duals. Precisely, we first provide some basic properties of Lipschitz algebras, which are important for metric geometry to know how metric properties are reflected in simple properties of Lipschitz functions. Then we show that all of these properties are equivalent to either uniform discreteness or finiteness of . Finally, some results concerning the character...
Some algebras without submultiplicative norms or positive functionals
We prove a conjecture of Yood regarding the nonexistence of submultiplicative norms on the algebra C(T) of all continuous functions on a topological space T which admits an unbounded continuous function. We also exhibit a quotient of C(T) which does not admit a nonzero positive linear functional. Finally, it is shown that the algebra L(X) of all linear operators on an infinite-dimensional vector space X admits no nonzero submultiplicative seminorm.
Some Applications of Convexity Theory to Banach Algebras.
Some characterizations of complex normed Q-algebras.
Some extremal properties of section spaces of Banach bundles and their duals.
Some homological properties of Banach algebras associated with locally compact groups
We investigate some homological notions of Banach algebras. In particular, for a locally compact group G we characterize the most important properties of G in terms of some homological properties of certain Banach algebras related to this group. Finally, we use these results to study generalized biflatness and biprojectivity of certain products of Segal algebras on G.
Some module cohomological properties of Banach algebras
We find some relations between module biprojectivity and module biflatness of Banach algebras and and their projective tensor product . For some semigroups , we study module biprojectivity and module biflatness of semigroup algebras .
Some notions of amenability for certain products of Banach algebras
For two Banach algebras and ℬ, an interesting product , called the θ-Lau product, was recently introduced and studied for some nonzero characters θ on ℬ. Here, we characterize some notions of amenability as approximate amenability, essential amenability, n-weak amenability and cyclic amenability between and ℬ and their θ-Lau product.
Some observations on local uniform boundedness principles
Some observations on local uniform boundedness principles. II
Some remarks about the three spaces problem in Banach algebras
Some remarks on derivations in Banach algebras and related results.
Some remarks on -algebras
We study Banach algebras that are quotients of uniform algebras and we show in particular that the class is stable by interpolation. We also show that , are algebras and that is a -algebra if and only if .
Some remarks on the surjectivity spectrum of linear operators
Some results about Banach compact algebras