Search results for "Operator space"

showing 8 items of 8 documents

Connected components in the space of composition operators onH∞ functions of many variables

2003

LetE be a complex Banach space with open unit ballBe. The structure of the space of composition operators on the Banach algebra H∞, of bounded analytic functions onBe with the uniform topology, is studied. We prove that the composition operators arising from mappings whose range lies strictly insideBe form a path connected component. WhenE is a Hilbert space or aCo(X)- space, the path connected components are shown to be the open balls of radius 2.

Discrete mathematicsAlgebra and Number TheoryApproximation propertyInfinite-dimensional vector functionHilbert spaceOperator theoryOperator spaceContinuous functions on a compact Hausdorff spacesymbols.namesakeOperator algebraBanach algebrasymbolsAnalysisMathematicsIntegral Equations and Operator Theory
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Basic Sequences in the Dual of a Fréchet Space

2001

Discrete mathematicsAlgebrac spaceBs spaceFréchet spaceGeneral MathematicsReflexive spaceOperator spaceSequence spaceComplete metric spaceMathematicsDual (category theory)Mathematische Nachrichten
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Weakly compact composition operators between algebras of bounded analytic functions

1999

Discrete mathematicsApplied MathematicsGeneral MathematicsBounded functionAnalytic capacityFinite-rank operatorCompact operatorOperator spaceCompact operator on Hilbert spaceMathematicsBounded operatorAnalytic functionProceedings of the American Mathematical Society
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QUASI *-ALGEBRAS OF OPERATORS AND THEIR APPLICATIONS

1995

The main facts of the theory of quasi*-algebras of operators acting in a rigged Hilbert space are reviewed. The particular case where the rigged Hilbert space is generated by a self-adjoint operator in Hilbert space is examined in more details. A series of applications to quantum theories are discussed.

Discrete mathematicsHilbert manifoldHilbert spaceStatistical and Nonlinear PhysicsRigged Hilbert spaceOperator spaceCompact operator on Hilbert spaceAlgebraPOVMsymbols.namesakeOperator algebraHermitian adjointsymbolsMathematical PhysicsMathematicsReviews in Mathematical Physics
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Bounded elements of C*-inductive locally convex spaces

2013

The notion of bounded element of C*-inductive locally convex spaces (or C*-inductive partial *-algebras) is introduced and discussed in two ways: The first one takes into account the inductive structure provided by certain families of C*-algebras; the second one is linked to the natural order of these spaces. A particular attention is devoted to the relevant instance provided by the space of continuous linear maps acting in a rigged Hilbert space.

Discrete mathematicsPositive elementApplied Mathematics010102 general mathematicsMathematics - Operator AlgebrasRigged Hilbert spaceMathematics - Rings and AlgebrasLF-spaceSpace (mathematics)01 natural sciencesOperator spaceBounded operatorBounded elements Inductive limit of C*-algebras Partial *-algebras010101 applied mathematics47L60 47L40Rings and Algebras (math.RA)Bounded functionLocally convex topological vector spaceFOS: Mathematics0101 mathematicsOperator Algebras (math.OA)Mathematics
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Absolutely summing operators on C[0,1] as a tree space and the bounded approximation property

2010

Abstract Let X be a Banach space. For describing the space P ( C [ 0 , 1 ] , X ) of absolutely summing operators from C [ 0 , 1 ] to X in terms of the space X itself, we construct a tree space l 1 tree ( X ) on X. It consists of special trees in X which we call two-trunk trees. We prove that P ( C [ 0 , 1 ] , X ) is isometrically isomorphic to l 1 tree ( X ) . As an application, we characterize the bounded approximation property (BAP) and the weak BAP in terms of X ∗ -valued sequence spaces.

Discrete mathematicsSequenceTree (descriptive set theory)Approximation propertyBounded functionInfinite-dimensional vector functionBanach spaceSpace (mathematics)Operator spaceAnalysisMathematicsJournal of Functional Analysis
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On coefficients of vector-valued Bloch functions

2004

Multiplier (Fourier analysis)Bloch sphereGeneral MathematicsMathematical analysisOperator spaceMathematicsStudia Mathematica
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Weyl's theorem for perturbations of paranormal operators

2007

A bounded linear operator T ∈ L(X) on a Banach space X is said to satisfy "Weyl's theorem" if the complement in the spectrum of the Weyl spectrum is the set of all isolated points of the spectrum which are eigenvalues of finite multiplicity. In this paper we show that if T is a paranormal operator on a Hilbert space, then T + K satisfies Weyl's theorem for every algebraic operator K which commutes with T.

Unbounded operatorPure mathematicsApplied MathematicsGeneral MathematicsHilbert spaceBanach spaceMathematics::Spectral TheoryCompact operatorOperator spaceBounded operatorsymbols.namesakesymbolsWeyl transformationContraction (operator theory)MathematicsProceedings of the American Mathematical Society
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