Results 81 to 90 of about 18,154 (228)
Commutative Banach Algebras Generated by Toeplitz Operators on the Bergman Space [PDF]
, 2022 Miguel Ángel Rodríguez Rodríguez
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Transactions of the London Mathematical Society, Volume 12, Issue 1, December 2025.Abstract In subwavelength physics, a challenging problem is to characterise the spectral properties of finite systems of subwavelength resonators. In particular, it is important to identify localised modes as well as bandgaps and associated mobility edges.
Habib Ammari +2 more
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Partially Isometric Toeplitz Operators [PDF]
Proceedings of the American Mathematical Society, 1965 It has been observed that the only Toeplitz operators that are isometric are those of the form To where q is an inner function on the unit disc (see e.g., [1, Theorem 8, Corollary 3]; the notation and terminology introduced there will be adhered to throughout this note).
Brown, Arlen, Douglas, R. G.
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Space‐Time Boundary Elements on Graded Meshes for 3D Elastodynamics
International Journal for Numerical Methods in Engineering, Volume 126, Issue 20, 30 October 2025.ABSTRACT The solution to the elastodynamic equations in the exterior of a polygonal or polyhedral domain or a screen exhibits singularities at corners and edges. This paper presents a space‐time boundary element method in 3D on algebraically graded meshes to resolve these singularities, based on recently obtained error estimates for the weakly singular
Alessandra Aimi +3 more
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Sensitivity of Perron and Fiedler Eigenpairs to Structural Perturbations of a Network
Numerical Linear Algebra with Applications, Volume 32, Issue 5, October 2025.ABSTRACT One can estimate the change of the Perron and Fiedler values for a connected network when the weight of an edge is perturbed by analyzing relevant entries of the Perron and Fiedler vectors. This is helpful for identifying edges whose weight perturbation causes the largest change in the Perron and Fiedler values.
Silvia Noschese, Lothar Reichel
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Dirac–Schrödinger operators, index theory and spectral flow
Journal of the London Mathematical Society, Volume 112, Issue 4, October 2025.Abstract In this article, we study generalised Dirac–Schrödinger operators in arbitrary signatures (with or without gradings), providing a general KK$\textnormal {KK}$‐theoretic framework for the study of index pairings and spectral flow. We provide a general Callias Theorem, which shows that the index (or the spectral flow, or abstractly the K ...
Koen van den Dungen
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Compact Operators on the Bergman Spaces with Variable Exponents on the Unit Disc of C
International Journal of Mathematics and Mathematical Sciences, 2018 We study the compactness of some classes of bounded operators on the Bergman space with variable exponent. We show that via extrapolation, some results on boundedness of the Toeplitz operators with general L1 symbols and compactness of bounded operators ...
Dieudonne Agbor
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Reducing Subspaces of the Dual Truncated Toeplitz Operator
Journal of Function Spaces, 2018 We define the dual truncated Toeplitz operators and give some basic properties of them. In particular, spectrum and reducing subspaces of some special dual truncated Toeplitz operator are characterized.
Yinyin Hu +4 more
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Normal Truncated Toeplitz Operators [PDF]
Complex Analysis and Operator Theory, 2017 The characterization of normal truncated Toepltiz operators is first given by Chalendar and Timotin. We give an elementary proof of their result without using the algebraic properties of truncated Toeplitz operators.
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Matrix Representations of Asymmetric Truncated Toeplitz Operators [PDF]
, 2020 Joanna Jurasik, Bartosz Łanucha
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