Berrabah Bendoukha, Hafida Bendahmane (2011)
Archivum Mathematicum
Let be the set of all bounded linear operators acting in Hilbert space and the set of all positive selfadjoint elements of . The aim of this paper is to prove that for every finite sequence of selfadjoint, commuting elements of and every natural number , the inequality holds.
Soares, G. (2009)
JIPAM. Journal of Inequalities in Pure & Applied Mathematics [electronic only]
M.H. Protter (1979)
Manuscripta mathematica
Bernd Carl (1985)
Annales de l'institut Fourier
The paper deals with covering problems and the degree of compactness of operators. The main part is devoted to relationships between entropy moduli and Kolmogorov (resp. Gelfand and approximation) numbers for operators which may be interpreted as counterparts to the classical Bernstein-Jackson inequalities for functions. Certain quantifications of results in the Riesz-Schauder-Theory are given. Finally, the largest distance between “the degree of approximation” and the “degree of compactness” of...
Mursaleen, S. M. H. Zaidi (1985)
Matematički Vesnik
S. Doplicher, F. Figliolini, D. Guido (1984)
Annales de l'I.H.P. Physique théorique
Mirzavaziri, M., Naranjani, K., Niknam, A. (2010)
Banach Journal of Mathematical Analysis [electronic only]
Erich Bohl, Ivo Marek (2005)
Applications of Mathematics
Our aim is to show a class of mathematical models in application to some problems of cell biology. Typically, our models are described via classical chemical networks. This property is visualized by a conservation law. Mathematically, this conservation law guarantees most of the mathematical properties of the models such as global existence and uniqueness of solutions as well as positivity of the solutions for positive data. These properties are consequences of the fact that the infinitesimal generators...
Mildred Hager (2006)
Annales de la faculté des sciences de Toulouse Mathématiques
Dans ce travail, nous considérons un opérateur différentiel simple ainsi que des perturbations. Alors que le spectre de l’opérateur non-perturbé est confiné à une droite à l’intérieur du pseudospectre, nous montrons pour les opérateurs perturbés que les valeurs propres se distribuent à l’intérieur du pseudospectre d’après une loi de Weyl.
María E. Ballve, P. Jiménez Guerra (1989)
Revista de la Real Academia de Ciencias Exactas Físicas y Naturales
Tibilov, K.T. (1999)
Vladikavkazskiĭ Matematicheskiĭ Zhurnal
P.H. Maserick, E.H. Youssfi (1992)
Mathematische Zeitschrift
Benedetto Silvestri (2009)
M. H. Castro, V. A. Menegatto, A. P. Peron (2012)
Colloquium Mathematicae
We analyze some aspects of Mercer's theory when the integral operators act on L²(X,σ), where X is a first countable topological space and σ is a non-degenerate measure. We obtain results akin to the well-known Mercer's theorem and, under a positive definiteness assumption on the generating kernel of the operator, we also deduce series representations for the kernel, traceability of the operator and an integration formula to compute the trace. In this way, we upgrade considerably similar results...
Khristo N. Boyadzhiev (2002)
Collectanea Mathematica
Mamontov, A.E. (2006)
Sibirskij Matematicheskij Zhurnal
Mamontov, A.E. (2006)
Sibirskij Matematicheskij Zhurnal
Wolfgang Arendt, Alexander V. Bukhvalov (1994)
Forum mathematicum
Igor Novitskiî (2005)
Open Mathematics
In this paper, we prove that every unbounded linear operator satisfying the Korotkov-Weidmann characterization is unitarily equivalent to an integral operator in L 2(R), with a bounded and infinitely smooth Carleman kernel. The established unitary equivalence is implemented by explicitly definable unitary operators.
P. Bonneau, Diedrich (1990)
Mathematische Annalen