Results 11 to 20 of about 4,584,260 (359)
Spectrum of a composition operator [PDF]
Proceedings of the American Mathematical Society, 1973 A composition operator is a linear operator induced on a subspace of K X {K^X} by a point transformation ϕ \phi on a set X (where K denotes the scalar field) by the formula T f ( x ) = f ∘ ϕ ( x )
William C. Ridge
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Composition operator on $l\sp{p}$ and its adjoint [PDF]
Proceedings of the American Mathematical Society, 1978 Let ϕ \phi be holomorphic and map the open unit disk into itself, and let C ϕ : f → f ∘ ϕ {C_\phi }:f \to f \circ \phi be the composition operator on H 2 {H^2} generated ...
R. K. Singh, B. Komal
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Composition operators isolated in the uniform operator topology [PDF]
Proceedings of the American Mathematical Society, 1981 It is is shown that ϕ \phi is an analytic map of the disc | z | > 1 \left | z \right | > 1 into itself such that ϕ \phi has radial limits of modulus 1 on a set of positive measure, then for 1 ⩽ p >
Earl Berkson
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Composition Operators and Endomorphisms [PDF]
Complex Analysis and Operator Theory, 2010 If $b$ is an inner function, then composition with $b$ induces an endomorphism, $ $, of $L^\infty(\mathbb{T})$ that leaves $H^\infty(\mathbb{T})$ invariant. We investigate the structure of the endomorphisms of $B(L^2(\mathbb{T}))$ and $B(H^2(\mathbb{T}))$ that implement $ $ through the representations of $L^\infty(\mathbb{T})$ and $H^\infty(\mathbb{T}
Courtney, Dennis +2 more
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Subnormal composition operators [PDF]
Proceedings of the American Mathematical Society, 1988 Let C C be the composition operator on L 2 ( X , Σ , m ) {L^2}(X,\Sigma ,m) given by C f = f ∘ T Cf = f \circ T , where T T is a Σ
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Compact composition operators on the Dirichlet space and capacity of sets of contact points [PDF]
, 2012 In this paper, we prove that for every compact set of the unit disk of logarithmic capacity 0, there exists a Schur function both in the disk algebra and in the Dirichlet space such that the associated composition operator is in all Schatten classes (of ...
Lefèvre, Pascal +3 more
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Demonstratio Mathematica, 2014 In this paper, we consider the Nemytskii operator (Hf)(t) = h(t, f(t)), generated by a given function h. It is shown that if H is globally Lipschitzian and maps the space of functions of bounded (p,2,α)-variation (with respect to a weight function α ...
Aziz Wadie
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An approach to elliptic equations with nonlinear gradient terms via a modulation framework
Bulletin of Mathematical Sciences, 2023 We consider a class of nonhomogeneous elliptic equations with fractional Laplacian and nonlinear gradient terms, namely [Formula: see text] in [Formula: see text], where [Formula: see text], [Formula: see text] is the nonlinearity, [Formula: see text ...
Lucas C. F. Ferreira, Wender S. Lagoin
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Composition operator induced by ?(z) = sz + t for which |s|?1, |t|<1 and |s|+|t|?1
مجلة بغداد للعلوم, 2010 We study in this paper the composition operator that is induced by ?(z) = sz + t. We give a characterization of the adjoint of composiotion operators generated by self-maps of the unit ball of form ?(z) = sz + t for which |s|?1, |t|
Baghdad Science Journal
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Composite operators in QCD [PDF]
Nuclear Physics B, 1992 We give a formula for the derivatives of a correlation function of composite operators with respect to the parameters (i.e., the strong fine structure constant and the quark mass) of QCD in four-dimensional euclidean space. The formula is given as spatial integration of the operator conjugate to a parameter. The operator product of a composite operator
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