Results 11 to 20 of about 1,398,064 (308)
Convex multivariate operator means [PDF]
Linear Algebra and its Applications, 2019 The dominant method for defining multivariate operator means is to express them as fix-points under a contraction with respect to the Thompson metric. Although this method is powerful, it crucially depends on monotonicity. We are developing a technique to prove the existence of multivariate operator means that are not necessarily monotone.
Hansen, Frank
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Ergodicity in strongly correlated systems [PDF]
Condensed Matter Physics, 2006 We present a concise and systematic, review of the ergodicity issue in strongly correlated systems. After giving a brief historical overview, we analyze the issue within the Green's function formalism by means of the equations of motion approach.
A.Avella, F.Mancini, E.Plekhanov
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Norms of some operators between weighted-type spaces and weighted Lebesgue spaces
AIMS Mathematics, 2023 We calculate the norms of several concrete operators, mostly of some integral-type ones between weighted-type spaces of continuous functions on several domains.
Stevo Stević
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Means in money exchange operations
Journal of Applied Mathematics and Computational Mechanics, 2023 It is observed that in some money exchange operations, the applied $n$ -variable mean $M$ should be self reciprocally-conjugate, i.e. it should satisfy the equality \[ M\left( x_{1},\ldots,x_{n}\right) M\left( \frac{1}{x_{1}},\ldots,\frac{1}{x_{n}} \right) =1,\quad x_{1},\ldots,x_{n}>0.
Jacek Bojarski, Janusz Matkowski
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New versions of refinements and reverses of Young-type inequalities with the Kantorovich constant
Special Matrices, 2023 Recently, some Young-type inequalities have been promoted. The purpose of this article is to give further refinements and reverses to them with Kantorovich constants.
Rashid Mohammad H. M., Bani-Ahmad Feras
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Mean ergodic semigroups of operators [PDF]
Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas, 2011 Research partially supported by MICINN and FEDER Project MTM2010-15200 and GV Project Prometeo/2008/101.
ALBANESE, Angela Anna +2 more
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Order of operators determined by operator mean [PDF]
Tohoku Mathematical Journal, 2015 Let $\sigma$ be an operator mean and $f$ a non-constant operator monotone function on $(0,\infty)$ associated with $\sigma$. If operators $A, B$ satisfy $0\le A \le B$, then it holds that $Y \sigma (tA+X) \le Y \sigma (tB+X)$ for any non-negative real number $t$ and any positive, invertible operators $X,Y$. We show that the condition $ Y \sigma (tA+X) \
Nagisa, Masaru, Uchiyama, Mitsuru
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OPERATOR MEANS IN JB-ALGEBRAS [PDF]
Reports on Mathematical Physics, 2021 In this paper, the notion of operator means in the setting of JB-algebras is introduced and their properties are studied. Many identities and inequalities are established, most of them have origins from operators on Hilbert space but they have different forms and connotations, and their proofs require techniques in JB-algebras.
Wang, Shuzhou, Wang, Zhenhua
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Weak-type endpoint bounds for Bochner–Riesz means for the Hermite operator
Comptes Rendus. Mathématique, 2022 We obtain weak-type $(p, p)$ endpoint bounds for Bochner–Riesz means for the Hermite operator $H = -\Delta + |x|^2$ in ${\mathbb{R}}^n, n\ge 2$ and for other related operators, for $1\le p\le 2n/(n+2)$, extending earlier results of Thangavelu and of ...
Chen, Peng +3 more
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Approximation properties of modified Jain-Gamma operators
Karpatsʹkì Matematičnì Publìkacìï, 2021 In the present paper, we study some approximation properties of a modified Jain-Gamma operator. Using Korovkin type theorem, we first give approximation properties of such operator.
S. Erdogan, A. Olgun
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