Search results for "C*-algebras"

showing 7 items of 37 documents

CQ*-algebras and noncommutative measure

2012

In this paper we continue the investigations in [4], [5], [8], [13], [14], [15], and [19], of the structure of quasi *-algebras and extend the results in [1] and [2]. Here, noncommutative Tp-spaces are shown to constitute examples of a class of Banach C*-modules called CQ*-algebras. Moreover, it is shown that any (strongly) *-semisimple proper CQ*-algebra (X ,A), with A a separable C*-algebra, can be represented as a CQ*-algebra of type Tp.

Settore MAT/05 - Analisi MatematicaCQ*-algebras.
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Operators in rigged Hilbert spaces: toward a spectral analysis

Settore MAT/05 - Analisi Matematicarigged Hilbert spaces partial *-algebras.
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Locally convex quasi $C^*$-normed algebras

2012

Abstract If A 0 [ ‖ ⋅ ‖ 0 ] is a C ∗ -normed algebra and τ a locally convex topology on A 0 making its multiplication separately continuous, then A 0 ˜ [ τ ] (completion of A 0 [ τ ] ) is a locally convex quasi ∗-algebra over A 0 , but it is not necessarily a locally convex quasi ∗-algebra over the C ∗ -algebra A 0 ˜ [ ‖ ⋅ ‖ 0 ] (completion of A 0 [ ‖ ⋅ ‖ 0 ] ). In this article, stimulated by physical examples, we introduce the notion of a locally convex quasi C ∗ -normed algebra, aiming at the investigation of A 0 ˜ [ τ ] ; in particular, we study its structure, ∗-representation theory and functional calculus.

Strong commutatively quasi-positive elementNormed algebraPure mathematicsApplied MathematicsRegular locally convex topologyRegular polygonStructure (category theory)Mathematics - Operator AlgebrasFOS: Physical sciencesLocally convex quasi C∗-normed algebraMathematical Physics (math-ph)Representation theoryquasi *-algebras C*-normsFunctional calculusMathematics::LogicCommutatively quasi-positive elementSettore MAT/05 - Analisi MatematicaFOS: MathematicsMultiplicationAlgebra over a fieldElement (category theory)Operator Algebras (math.OA)AnalysisMathematical PhysicsMathematics
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Quasi *-algebras and generalized inductive limits of C*-algebras

2011

inductive limitJordan algebraGeneral MathematicsSubalgebraCurrent algebraUniversal enveloping algebraFiltered algebraAlgebraC*-algebrasSettore MAT/05 - Analisi MatematicaQuasi *-algebraAlgebra representationDivision algebraCellular algebraMathematics
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A note on *-derivations of partial *-algebras

2012

A definition of *-derivation of partial *-algebra through a sufficient family of ips-forms is proposed.

partial *-algebras sesquilinear forms *-derivationSettore MAT/05 - Analisi Matematica
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Locally convex quasi *-algebras: basic aspects and commutative case

2010

quasi *-algebrasSettore MAT/05 - Analisi Matematica
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Extensions of representable linear functionals to unitized quasi *-algebras

2013

This paper starts from noting that, under certain conditions, *-representability and extensibility to the unitized *-algebra of a positive linear functional, defined on a *-algebra without unit, are equivalent. Here some conditions for the equivalence of the same concepts for a hermitian linear functional defined on a quasi *-algebra $(\A,\Ao)$ without unit are given. The approach is twofold: on the one hand, conditions for the equivalence are exhibited by introducing a condition for the *- representability of the extension of a *-representable functional to the unitized quasi *-algebra, on the other hand a *-representable extension to the unitization of a hermitian linear functional by mea…

unitized quasi *-algebras.Settore MAT/05 - Analisi Matematica*-representable linear functional
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