Abstract
We consider the Sturm-Liouville operator L(y) = −d 2 y/dx 2 + q(x)y in the space L 2[0, π], where the potential q(x) is a complex-valued distribution of the first order of singularity; namely, q(x) = ut’(x), where u ∈ L 2[0, π]. (The derivative is understood in the sense of distributions.) We study the uniform equiconvergence on the entire interval [0, π] of the expansions of a function f ∈ L 2 in the system of eigenfunctions and associated functions of the operator L with the Fourier trigonometric series expansion. We also estimate the equiconvergence rate.
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Savchuk, A.M. and Shkalikov, A.A., Sturm-Liouville Operators with Singular Potentials, Mat. Zametki, 1999, vol. 66, no. 6, pp. 897–912.
Savchuk, A.M. and Shkalikov, A.A., Sturm-Liouville Operators with Distribution Potentials, Tr. Mosk. Mat. Obs., 2003, vol. 64, pp. 159–219.
Savchuk, A.M., On Eigenfunctions of the Sturm-Liouville Operator with Potentials from Sobolev Spaces, arXiv, 2010, no. 1003.3172.
Sadovnichaya, I.V., Equiconvergence of Expansions in Series in Eigenfunctions of Sturm-Liouville Operators with Distribution Potentials, Mat. Sb., 2010, vol. 201, no. 9, pp. 61–76.
Sadovnichaya, I.V., On the Rate of Equiconvergence of Expansions in Series in a Trigonometric System and in Eigenfunctions of the Sturm-Liouville Operator with Distribution Potential, Differ. Uravn., 2008, vol. 44, no. 5, pp. 656–664.
Shveikina, O.A., On the Asymptotics of Eigenfunctions of Sturm-Liuoville Operators with Distribution Potentials, Differ. Uravn., 2013, vol. 49, no. 8, pp. 985–992.
Shveikina, O.A., Theorems on Asymptotics of Sturm-Liouville Singular Operators with Various Boundary Conditions, Differ. Uravn., 2014, vol. 50, no. 5, pp. 626–635.
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Original Russian Text © O.A. Shveikina, 2015, published in Differentsial’nye Uravneniya, 2015, Vol. 51, No. 2, pp. 174–182.
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Shveikina, O.A. Equiconvergence theorems for singular Sturm-Liouville operators with various boundary conditions. Diff Equat 51, 177–185 (2015). https://doi.org/10.1134/S0012266115020032
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DOI: https://doi.org/10.1134/S0012266115020032