Properties and Convergence Analysis of Orthogonal Polynomials, Reproducing Kernels, and Bases in Hilbert Spaces Associated with Norm-Attainable Operators

Mogoi N. Evans *

Department of Mathematics and Statistics, Kaimosi Friends University, P.O. BOX 385-50309, Kaimosi, Kenya.

*Author to whom correspondence should be addressed.


This research paper delves into the properties and convergence behaviors of various sequences of orthogonal polynomials, reproducing kernels, and bases within Hilbert spaces governed by norm-attainable operators. Through rigorous analysis, the study establishes the completeness of the sequences of monic orthogonal polynomials and orthonormal polynomials, highlighting their comprehensive representation and approximation capabilities in the Hilbert space. The paper also demonstrates the completeness and density attributes of the sequence of normalized reproducing kernels, showcasing its effective role in capturing the intrinsic structure of the space. Additionally, the research investigates the uniform convergence of these sequences, revealing their convergence to essential operators within the Hilbert space. Ultimately, these results contribute to both theoretical understanding and practical applications in various fields by providing insights into function approximation and representation within this mathematical framework.

Keywords: Norm-attainable operators, hilbert spaces, orthogonal polynomials, reproducing kernels, completeness, density, uniform convergence, basis, approximation, function representation, mathematical analysis, convergence behavior

How to Cite

Evans, M. N. (2023). Properties and Convergence Analysis of Orthogonal Polynomials, Reproducing Kernels, and Bases in Hilbert Spaces Associated with Norm-Attainable Operators. Asian Research Journal of Mathematics, 19(11), 1–10.


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