Results 31 to 40 of about 99,725 (136)
Scattering matrices and Weyl functions [PDF]
, 2006 For a scattering system $\{A_\Theta,A_0\}$ consisting of selfadjoint extensions $A_\Theta$ and $A_0$ of a symmetric operator $A$ with finite deficiency indices, the scattering matrix $\{S_\gT(\gl)\}$ and a spectral shift function $\xi_\Theta$ are ...
Behrndt, Jussi +2 more
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Well-bounded and scalar-type spectral operators on spaces not containing 𝑐₀ [PDF]
Proceedings of the American Mathematical Society, 1989 It is known that a necessary and sufficient condition for a well-bounded operator on a weakly complete complex Banach space to be scalar-type spectral is that its decomposition of the identity be of bounded variation. We show in this paper that this condition is necessary and sufficient exactly when the Banach space does not contain a subspace ...
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Boolean algebras of projections and resolutions of the identity of scalar-type spectral operators [PDF]
Proceedings of the Edinburgh Mathematical Society, 1997 Let Μ be a Bade complete (or σ-complete) Boolean algebra of projections in a Banach space X. This paper is concerned with the following questions: When is Μ equal to the resolution of the identity (or the strong operator closure of the resolution of the identity) of some scalar-type spectral operator T (with σ(T) ⊆ ℝ) in X?
De Pagter, B., Ricker, W. J.
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The Pauli equation with complex boundary conditions
, 2012 We consider one-dimensional Pauli Hamiltonians in a bounded interval with possibly non-self-adjoint Robin-type boundary conditions. We study the influence of the spin-magnetic interaction on the interplay between the type of boundary conditions and the ...
Albeverio S +25 more
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Scalar-type spectral operators and holomorphic semigroups
Semigroup Forum, 1986 We show that a linear operator (possibly unbounded), A, on a reflexive Banach space, X, is a scalar-type spectral operator, with non-negative spectrum, if and only if the following conditions hold. (1) A generates a uniformly bounded holomorphic semigroup \(\{e^{- zA}\}_{Re(z)\geq 0}.\) (2) If \(F_ N(s)\equiv \int^{N}_{-N}\frac{\sin (sr)}{r}e^{irA}dr\),
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On scalar type spectral operators, infinite differentiable and Gevrey ultradifferentiable C0‐semigroups [PDF]
International Journal of Mathematics and Mathematical Sciences, 2004 Necessary and sufficient conditions for a scalar type spectral operator in a Banach space to be a generator of an infinite differentiable or a Gevrey ultradifferentiable C0‐semigroup are found, the latter formulated exclusively in terms of the operator′s spectrum.
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On scalar-type spectral operators and Carleman ultradifferentiable C 0-semigroups [PDF]
Ukrainian Mathematical Journal, 2008 Necessary and sufficient conditions for a scalar-type spectral operator in a Banach space to be a generator of a Carleman ultradifferentiable C 0-semigroup are found. The conditions are formulated exclusively in terms of the spectrum of the operator.
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Pseudo-differential operators, Wigner transform and Weyl systems on type I locally compact groups [PDF]
, 2017 Let G be a unimodular type I second countable locally compact group and let Gb be its unitary dual. We introduce and study a global pseudo-differential calculus for operator-valued symbols defined on G × Gb , and its relations to suitably defined Wigner ...
Mantoiu, M, Ruzhansky, M
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The Sums and Products of Commuting AC-Operators
International Journal of Industrial Engineering and Production Research, 2007 : In this paper, we exhibit new conditions for the sum of two commuting AC-operators to be again an AC-operator. In particular, this is satisfied on Hilbert space when one of them is a scalar-type spectral operator.
M.B Ghaemi, p. Spain
doaj
, 2007 The recent extension of the standard model to include massive neutrinos in the framework of noncommutative geometry and the spectral action principle involves new scalar fields and their interactions with the usual complex scalar doublet.
Connes A. +7 more
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