Semigroup crossed products and Hecke algebras arising from number fields.
Semigroups and Hilbert's fifth problem
Separation of unitary representations of exponential Lie groups.
Sets of p-multiplicity in locally compact groups
We initiate the study of sets of p-multiplicity in locally compact groups and their operator versions. We show that a closed subset E of a second countable locally compact group G is a set of p-multiplicity if and only if is a set of operator p-multiplicity. We exhibit examples of sets of p-multiplicity, establish preservation properties for unions and direct products, and prove a p-version of the Stone-von Neumann Theorem.
Siegel measures.
Simple quotients of group -algebras for two step nilpotent groups and connected Lie groups
Some aspects of harmonic analysis on free groups
Some groups whose reduced -algebra is simple
Some properties of groups without the property P1.
Some Remarks on Automorphisms of Bounded Displacement and Bounded Cocycles.
Some remarks on C*-bigebras and duality.
Some remarks on induced representations of infinite discrete groups.
Some Remarks on L1(G).
Some results on submodules of
Some Results on Affine Transformations of Compact Groups.
Some theorems on hemigroups.
Sottogruppi topologicamente quasi-normali dei gruppi localmente compatti
Specker-Kompaktifizierungen von lokal kompakten topologischen Gruppen.
Spectral Pairs in Cartesian Coordinates.
Spectral subspaces and non-commutative Hilbert transforms
Let G be a locally compact abelian group and ℳ be a semifinite von Neumann algebra with a faithful semifinite normal trace τ. We study Hilbert transforms associated with G-flows on ℳ and closed semigroups Σ of Ĝ satisfying the condition Σ ∪ (-Σ) = Ĝ. We prove that Hilbert transforms on such closed semigroups satisfy a weak-type estimate and can be extended as linear maps from L¹(ℳ,τ) into . As an application, we obtain a Matsaev-type result for p = 1: if x is a quasi-nilpotent compact operator...