Results 31 to 40 of about 2,695 (277)
Eigenvalue Bound for Schrödinger Operators with Unbounded Magnetic Field
Reports on Mathematical Physics, 2020 In this paper we consider magnetic Schroedinger operators on the two-dimensional unit disk with a radially symmetric magnetic field which explodes to infinity at the boundary. We prove a bound for the eigenvalue moments and a bound for the number of negative eigenvalues for such operators.
Barseghyan, Diana, Schneider, Baruch
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Unbounded B-Fredholm operators on Hilbert spaces [PDF]
, 2008 This paper is concerned with the study of a class of closed linear operators densely defined on a Hilbert space H and called B-Fredholm operators.
Berkani, M. +3 more
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Approximation of functions with linear positive operators which fix {1, φ} and {1, φ2}
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2020 In this manuscript, linear and positive operators described on bounded and unbounded intervals that fix the function sets {1, φ} and {1, φ2} such that φ ∈ C[0, 1] are presented. Then we present different types of operators by choosing different functions
Usta Fuat
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Bounded and unbounded operators between Köthe spaces [PDF]
Studia Mathematica, 2002 The authors study in terms of the corresponding Köthe matrices when every continuous linear operator between two Köthe spaces is bounded, the consequences of the existence of unbounded continuous linear operators, and related topics.
Djakov, P. B., Ramanujan, M. S.
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Fractional powers of higher-order vector operators on bounded and unbounded domains
Proceedings of the Edinburgh Mathematical Society, 2022 AbstractUsing the $H^{\infty }$-functional calculus for quaternionic operators, we show how to generate the fractional powers of some densely defined differential quaternionic operators of order $m\geq 1$, acting on the right linear quaternionic Hilbert space $L^{2}(\Omega,\mathbb {C}\otimes \mathbb {H})$. The operators that we consider are of the type
Baracco, L +3 more
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The Atkinson Theorem in Hilbert C*-Modules over C*-Algebras of Compact Operators
Abstract and Applied Analysis, 2007 The concept of unbounded Fredholm operators on Hilbert C*-modules over an arbitrary C*-algebra is discussed and the Atkinson theorem is generalized for bounded and unbounded Feredholm operators on Hilbert C*-modules over C*-algebras of compact operators.
A. Niknam, K. Sharifi
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Nonhomogeneous Dirichlet Problems with Unbounded Coefficient in the Principal Part
Axioms, 2022 The main result of the paper establishes the existence of a bounded weak solution for a nonlinear Dirichlet problem exhibiting full dependence on the solution u and its gradient ∇u in the reaction term, which is driven by a p-Laplacian-type operator with
Dumitru Motreanu
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A NOTE ON A TWO-PARAMETER FAMILY OF OPERATORS ${\MATHCAL A}^{B,C}$ ON WEIGHTED BERGMAN SPACES
Проблемы анализа, 2019 In this article, we prove that the two-parameter family of operators Ab,c is bounded on the weighted Bergman spaces B p α+c−1 if α + 2 < p and unbounded if α + 2 = p.
S. Naik, P. K. Nath
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Approximation of the Hilbert transform in the Lebesgue spaces
Journal of Numerical Analysis and Approximation Theory, 2023 The Hilbert transform plays an important role in the theory and practice of signal processing operations in continuous system theory because of its relevance to such problems as envelope detection and demodulation, as well as its use in relating the ...
Rashid Aliev, Lale Alizade
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The essential numerical range for unbounded linear operators [PDF]
, 2020 We introduce the concept of essential numerical range W_e(T) for unbounded Hilbert space operators T and study its fundamental properties including possible equivalent characterizations and perturbation results.
Bögli, Sabine +2 more
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