Results 11 to 20 of about 315,257 (270)
A generalization of Kantorovich operators for convex compact subsets [PDF]
, 2016 In this paper we introduce and study a new sequence of positive linear operators acting on function spaces defined on a convex compact subset. Their construction depends on a given Markov operator, a positive real number and a sequence of probability ...
Altomare, Francesco +3 more
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ON LOCAL APPROXIMATION OF POSITIVE OPERATORS
Demonstratio Mathematica, 2002 The main purpose of the paper is to extend some up-down theorems obtained by \textit{G. J. H. M. Buskes, P. G. Dodds, B. de Patger} and \textit{A. R. Schep} [Indag. Math. 48, 1--9 (1986; Zbl 0597.46009)] who proved that if \(E\) is a Banach lattice with quasi-interior points, \(F\) is a Dedekind complete Riesz space and \(\tilde F_n\) separates the ...
Alpay, Şafak, UYAR, AYŞE
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Approximation by positive operators
Linear Algebra and its Applications, 1992 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Bhatia, Rajendra, Kittaneh, Fuad
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APPROXIMATION OF CLASSES OF PERIODIC MULTIVARIABLE FUNCTIONS BY LINEAR POSITIVE OPERATORS [PDF]
, 2006 In an N-dimensional space, we consider the approximation of classes of translation-invariant periodic functions by a linear operator whose kernel is the product of two kernels one of which is positive.
Bushev, Dmytro Mykolayovych +3 more
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Iteration of positive approximation operators
Journal of Approximation Theory, 1970 AbstractWe present an analysis of the limit behavior of the k(n)-th iterates of positive linear approximation operators Ln, as n and k(n) tend to infinity. For various classes of operators the limit semigroup is explicitly identified. Two applications of the results are given: (a) identification of functions f satisfying Ln f ⩾ f for all n, for a ...
Karlin, S, Ziegler, Z
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Approximation numbers of composition operators on $H^p$ spaces of Dirichlet series [PDF]
, 2015 By a theorem of Bayart, $\varphi$ generates a bounded composition operator on the Hardy space $\Hp$of Dirichlet series ($1\le p1/2$ if $c_0=0$ and is either identically zero or maps the right half-plane into itself if $c_0$ is positive.
Bayart, Frédéric +2 more
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Unitary approximation of positive operators
Illinois Journal of Mathematics, 1980 Of concern are some operators inequalities arising in quantum chemistry. Let $A$ be a positive operator on a Hilbert space $\mathcal{H}$. We consider the minimization of $||U-A||_{p}$ as $U$ ranges over the unitary operators in $\mathcal{H}$ and prove that in most cases the minimum is attained when $U$ is the identity operator. The norms considered are
Aiken, John G. +2 more
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Large N limit of SO(N) gauge theory of fermions and bosons [PDF]
, 2002 In this paper we study the large N_c limit of SO(N_c) gauge theory coupled to a Majorana field and a real scalar field in 1+1 dimensions extending ideas of Rajeev. We show that the phase space of the resulting classical theory of bilinears, which are the
Aoki K. +18 more
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Approximation numbers of composition operators on the $H^2$ space of Dirichlet series [PDF]
, 2014 By a theorem of Gordon and Hedenmalm, $\varphi$ generates a bounded composition operator on the Hilbert space $\mathscr{H}^2$ of Dirichlet series $\sum_n b_n n^{-s}$ with square-summable coefficients $b_n$ if and only if $\varphi(s)=c_0 s+\psi(s)$, where
Queffélec, Hervé, Seip, Kristian
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Approximation numbers of weighted composition operators [PDF]
, 2016 We study the approximation numbers of weighted composition operators $f\mapsto w\cdot(f\circ\varphi)$ on the Hardy space $H^2$ on the unit disc. For general classes of such operators, upper and lower bounds on their approximation numbers are derived. For
Lechner, Gandalf +3 more
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