Results 1 to 10 of about 221,647 (311)
On Constructing Informationally Complete Covariant Positive Operator-Valued Measures [PDF]
Entropy, 2023 We study a projective unitary representation of the product G=G˜×G, where G is a locally compact Abelian group and G^ is its dual consisting of characters on G.
Grigori Amosov
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Generalized Cauchy–Schwarz Inequalities and A-Numerical Radius Applications
Axioms, 2023 The purpose of this research paper is to introduce new Cauchy–Schwarz inequalities that are valid in semi-Hilbert spaces, which are generalizations of Hilbert spaces.
Najla Altwaijry +2 more
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Tikrit Journal of Pure Science, 2023 In this paper we generalize the Fuglede-Putnam theorem to non-normal operators to posinormal operator and co-posinormal operators. Also we prove this theorem to supra class posinormal operators (called supraposinormal operator) and co-supra class ...
Mahmood Kamil Shihab
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Products of Positive Operators [PDF]
Complex Analysis and Operator Theory, 2021 AbstractOn finite dimensional spaces, it is apparent that an operator is the product of two positive operators if and only if it is similar to a positive operator. Here, the class $${\mathcal {L}^{+\,2}}$$ L +
Maximiliano Contino +3 more
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Positive operators as commutators of positive operators [PDF]
Studia Mathematica, 2019 20 ...
Drnovšek, Roman, Kandić, Marko
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On the Joint A-Numerical Radius of Operators and Related Inequalities
Mathematics, 2023 In this paper, we study p-tuples of bounded linear operators on a complex Hilbert space with adjoint operators defined with respect to a non-zero positive operator A.
Najla Altwaijry +2 more
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More on the extension of linear operators on Riesz spaces
Karpatsʹkì Matematičnì Publìkacìï, 2022 The classical Kantorovich theorem asserts the existence and uniqueness of a linear extension of a positive additive mapping, defined on the positive cone $E^+$ of a Riesz space $E$ taking values in an Archimedean Riesz space $F$, to the entire space $E$.
O.G. Fotiy, A.I. Gumenchuk, M.M. Popov
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Restricted Testing for Positive Operators [PDF]
The Journal of Geometric Analysis, 2021 We prove that for certain positive operators $T$, such as the Hardy-Littlewood maximal function and fractional integrals, there is a constant $D>1$, depending only on the dimension $n$, such that the two weight norm inequality \begin{equation*} \int_{\mathbb{R}^{n}}T\left( fσ\right) ^{2}dω\leq C\int_{\mathbb{ R}^{n}}f^{2}dσ\end{equation*} holds for ...
Hytönen, T., Li, K., Sawyer, E.
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A New Seminorm for d-Tuples of A-Bounded Operators and Their Applications
Mathematics, 2023 The aim of this paper was to introduce and investigate a new seminorm of operator tuples on a complex Hilbert space H when an additional semi-inner product structure defined by a positive (semi-definite) operator A on H is considered.
Najla Altwaijry +2 more
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Inequalities and Reverse Inequalities for the Joint A-Numerical Radius of Operators
Axioms, 2023 In this paper, we aim to establish several estimates concerning the generalized Euclidean operator radius of d-tuples of A-bounded linear operators acting on a complex Hilbert space H, which leads to the special case of the well-known A-numerical radius ...
Najla Altwaijry +2 more
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