Results 11 to 20 of about 281,509 (319)
Exponential Operators, Dobinski Relations and Summability [PDF]
Journal of Physics: Conference Series, 2005 We investigate properties of exponential operators preserving the particle number using combinatorial methods developed in order to solve the boson normal ordering problem.
A Gawron +10 more
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Ibragimov–Gadjiev operators preserving exponential functions
Journal of Inequalities and ApplicationsIn this paper, a modification of general linear positive operators introduced by Ibragimov and Gadjiev in 1970 is constructed. It is shown that this modification preserves exponential mappings and also contains modified Bernstein-, Szász- and Baskakov ...
Serap Herdem
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Semi-Exponential Operators [PDF]
Symmetry, 2021 In this paper we study approximation properties of exponential-type operators for functions from exponential weighted spaces. We focus on some modifications of these operators and we derive a new example of such operators. A probabilistic approach for these modifications is also demonstrated.
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Exponentially Dichotomous Operators and Applications [PDF]
, 2008 Cornelis van der Mee
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Bernstein Operators for Exponential Polynomials [PDF]
Constructive Approximation, 2008 Let $L$ be a linear differential operator with constant coefficients of order $n$ and complex eigenvalues $λ_{0},...,λ_{n}$. Assume that the set $U_{n}$ of all solutions of the equation $Lf=0$ is closed under complex conjugation. If the length of the interval $[ a,b] $ is smaller than $π/M_{n}$, where $M_{n}:=\max \left\{| \text{Im}% λ_{j}| :j=0,...,n ...
Aldaz, J. M. +2 more
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Exponentials of bounded normal operators [PDF]
Colloquium Mathematicum, 2013 The present paper is mainly concerned with equations involving exponentials of bounded normal operators. Conditions implying commutativity of those normal operators are given. This is carried out without the known $2 i$-congruence-free hypothesis. It is also a continuation of a recent work by the corresponding author.
Chaban, Aicha, Mortad, Mohammed Hichem
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Approximately disentangling exponential operators [PDF]
Journal of Mathematical Physics, 2010 A new method for the approximate disentangling of exponential operators based on the Baker–Campbell–Haussdorff theorem is suggested and implemented in a computer program. The operators to be disentangled must form a finite-dimensional Lie algebra. The accuracy of the method is tested and demonstrated in several explicitly calculated examples, where ...
Scholz, Daniel +2 more
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The spaces of exponential type vectors of complex degrees of positive operators
Karpatsʹkì Matematičnì Publìkacìï, 2013 New classes of interpolation spaces of exponential type vectors of complex degrees of positive operators are defined. Properties of the approximation spaces generated by the considered interpolation spaces are investigated.
M. I. Dmytryshyn
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Decomposition of Time-Ordered Products and Path-Ordered Exponentials [PDF]
, 1998 We present a decomposition formula for $U_n$, an integral of time-ordered products of operators, in terms of sums of products of the more primitive quantities $C_m$, which are the integrals of time-ordered commutators of the same operators. The resulting
Lam, C. S.
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Generalized Exponential Trichotomies for Abstract Evolution Operators on the Real Line
Journal of Function Spaces and Applications, 2013 This paper considers two trichotomy concepts in the context of abstract evolution operators. The first one extends the notion of exponential trichotomy in the sense of Elaydi-Hajek for differential equations to abstract evolution operators, and it is a ...
Nicolae Lupa, Mihail Megan
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