Results 21 to 30 of about 220,336 (311)
Indefinite Hamiltonian systems whose Titchmarsh–Weyl coefficients have no finite generalized poles of non-positive type [PDF]
, 2013 The two-dimensional Hamiltonian system (*) y'(x)=zJH(x)y(x), x∈(a,b), where the Hamiltonian H takes non-negative 2x2-matrices as values, and $J:= \begin{pmatrix} 0 & -1 \\ 1 & 0 \end{pmatrix}$, has attracted a lot of interest over the past decades ...
Harald Woracek +3 more
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Around the Furuta inequalitythe operator inequalities (AB2A)¾≤ABA≤A3
International Journal of Mathematics and Mathematical Sciences, 1995 For positive operators A and B with A invertible it is shown that (AB2A)½≤A2 implies (AB2A)¾≤ABA. The inequalities in the title for 0≤B≤A are then derived as a conquence.
Derming Wang
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On further refinements for Young inequalities
Open Mathematics, 2018 In this paper sharp results on operator Young’s inequality are obtained. We first obtain sharp multiplicative refinements and reverses for the operator Young’s inequality.
Furuichi Shigeru, Moradi Hamid Reza
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On the Positive Operator Solutions to an Operator Equation [PDF]
ISRN Mathematical Analysis, 2013 The necessary conditions and the sufficient condition for the existence of positive operator solutions to the operator equation Xs+A*X-tA=Q are established. An iterative method for obtaining the positive operator solutions is proposed.
Yang, Kai-Fan +2 more
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ON SOME INEQUALITIES FOR 𝜏 -MEASURABLE OPERATORS
Проблемы анализа, 2019 This paper deals with the Choi’s inequality for measurable operators affiliated with a given von Neumann algebra. Some Young and Cauchy-Schwarz type inequalities for 𝜏 -measurable operators are also given.
S. M. Davarpanah +2 more
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Experiments with a Positivity-Preserving Operator [PDF]
Experimental Mathematics, 2008 We consider some multivariate rational functions which have (or are conjectured to have) only positive coefficients in their series expansion. We consider an operator that preserves positivity of series coefficients, and apply the inverse of this operator to the rational functions.
Manuel Kauers, Doron Zeilberger
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Bulletin of the Korean Mathematical Society, 2002 Summary: We study the properties of positive-normal operators and show that Weyl's theorem holds for some totally positive-normal operators.
Jeon, In Ho +3 more
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Random positive operator valued measures [PDF]
, 2022 We introduce several notions of random positive operator valued measures (POVMs), and we prove that some of them are equivalent. We then study statistical properties of the effect operators for the canonical examples, starting from the limiting ...
Jivulescu MA, Heinosaari T, Nechita I
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High order singular rank one perturbations of a positive operator
, 2005 In this paper self-adjoint realizations in Hilbert and Pontryagin spaces of the formal expression L-alpha = L + psi are discussed and compared. Here L is a positive self-adjoint operator in a Hilbert space H with inner product , a is a real parameter ...
Dijksma, A +3 more
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Boundary value problems for partial differential equations with piecewise contant delay
International Journal of Mathematics and Mathematical Sciences, 1991 The influence of certain discontinuous delays on the behavior of solutions to some typical equations of mathematical physics is studied.
Joseph Wiener
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