A commutativity theorem for Banach algebras
A completely bounded characterization of operator algebras.
A Contribution to Segal Algebras.
A property for locally convex *-algebras related to property (T) and character amenability
For a locally convex *-algebra A equipped with a fixed continuous *-character ε (which is roughly speaking a generalized F*-algebra), we define a cohomological property, called property (FH), which is similar to character amenability. Let be the space of continuous functions with compact support on a second countable locally compact group G equipped with the convolution *-algebra structure and a certain inductive topology. We show that has property (FH) if and only if G has property (T). On...
A remark concerning commutativity modulo radical in Banach algebras
A spectral mapping theorem for Banach modules
Let G be a locally compact abelian group, M(G) the convolution measure algebra, and X a Banach M(G)-module under the module multiplication μ ∘ x, μ ∈ M(G), x ∈ X. We show that if X is an essential L¹(G)-module, then for each measure μ in reg(M(G)), where denotes the operator in B(X) defined by , σ(·) the usual spectrum in B(X), sp(X) the hull in L¹(G) of the ideal , μ̂ the Fourier-Stieltjes transform of μ, and reg(M(G)) the largest closed regular subalgebra of M(G); reg(M(G)) contains all...
Algebras de Banach de medidas vectoriales.
Amenability for discrete convolution semigroup algebras.
Antisymmetric operator algebras, II
Bounded elements in certain topological partial *-algebras
We continue our study of topological partial *-algebras, focusing on the interplay between various partial multiplications. The special case of partial *-algebras of operators is examined first, in particular the link between strong and weak multiplications, on one hand, and invariant positive sesquilinear (ips) forms, on the other. Then the analysis is extended to abstract topological partial *-algebras, emphasizing the crucial role played by appropriate bounded elements, called ℳ-bounded. Finally,...
Bundles of Banach algebras.
Closed ideals in topological algebras: a characterization of the topological -algebra
Let be a uniformly closed and locally m-convex -algebra. We obtain internal conditions on stated in terms of its closed ideals for to be isomorphic and homeomorphic to , the -algebra of all the real continuous functions on a normal topological space endowed with the compact convergence topology.
Compact elements of Banach Algebras
Decompositions of non-contractive operator-valued representations of Banach algebras
Derivations, Commutators and the Radical.
Dual Banach algebras: representations and injectivity
We study representations of Banach algebras on reflexive Banach spaces. Algebras which admit such representations which are bounded below seem to be a good generalisation of Arens regular Banach algebras; this class includes dual Banach algebras as defined by Runde, but also all group algebras, and all discrete (weakly cancellative) semigroup algebras. Such algebras also behave in a similar way to C*- and W*-algebras; we show that interpolation space techniques can be used in place of GNS type arguments....
Einfache Moduln über gewissen Banachschen Algebren: Ein Imprimitivitätssatz .
Extension of representations in quasi *-algebras
FF-Banachverbandsalgebren.
Finite rank elements in semisimple Banach algebras
Let A be a semisimple Banach algebra. We define the rank of a nonzero element a in the socle of A to be the minimum of the number of minimal left ideals whose sum contains a. Several characterizations of rank are proved.