Skip to main content
Log in

Loaded differential operators: Convergence of spectral expansions

  • Ordinary Differential Equations
  • Published:
Differential Equations Aims and scope Submit manuscript

Abstract

We study the convergence rate of biorthogonal series expansions of functions in systems of root functions of a broad class of loaded even-order differential operators defined on a finite interval. These expansions are compared with the Fourier trigonometric series expansions of the same functions in an integral metric on any interior compact set of the main interval or on the entire interval. We obtain estimates for the equiconvergence rate of these expansions.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Lomov, I.S., A Coefficient Condition for the Convergence of Biorthogonal Expansions of Functions in L p(, 1), Differ. Uravn., 1998, vol. 34, no. 1, pp. 31–39.

    MathSciNet  Google Scholar 

  2. Lomov, I.S., On the Influence of the Degree of Integrability of Coefficients of Differential Operators on the Equiconvergence Rate of Spectral Expansions. I, Differ. Uravn., 1998, vol. 34, no. 5, pp. 619–628; II, no. 8, pp. 1066–1077.

    MathSciNet  Google Scholar 

  3. Lomov, I.S., On the Local Convergence of Biorthogonal Series Associated with Differential Operators with Nonsmooth Coefficients. I, Differ. Uravn., 2001, vol. 37, no. 3, pp. 328–342; II, no. 5, pp. 648–660.

    MathSciNet  Google Scholar 

  4. Lomov, I.S., Convergence of Biorthogonal Expansions of Functions on an Interval for Higher-Order Differential Operators, Differ. Uravn., 2005, vol. 41, no. 5, pp. 632–646.

    MathSciNet  Google Scholar 

  5. Il’in, V.A., Spektral’naya teoriya differentsial’nykh operatorov (Spectral Theory of Differential Operators), Moscow: Nauka, 1991.

    MATH  Google Scholar 

  6. Il’in, V.A., Necessary and Sufficient Conditions for Spatial Decompositions To Be Bases and To Be Equiconvergent with the Trigonometric Series. I, Differ. Uravn., 1980, vol. 16, no. 5, pp. 771–794; II, no. 6, pp. 980–1009.

    MATH  Google Scholar 

  7. Il’in, V.A., Equiconvergence, with the Trigonometric Series, of Expansions in Root Functions of the One-Dimensional Schrödinger Operator with Complex Potential in the Class L 1, Differ. Uravn., 1991, vol. 27, no. 4, pp. 577–597.

    Google Scholar 

  8. Lomov, I.S., The Basis Property of Root Vectors of Loaded Second-Order Differential Operators on an Interval, Differ. Uravn., 1991, vol. 27, no. 1, pp. 80–93.

    MathSciNet  Google Scholar 

  9. Nakhushev, A.M., Loaded Equations and Their Applications, Differ. Uravn., 1983, vol. 19, no. 1, pp. 86–94.

    MathSciNet  Google Scholar 

  10. Lomov, I.S., A Theorem on the Unconditional Basis Property of Root Vectors of Second-Order Weighted Differential Operators, Differ. Uravn., 1991, vol. 27, no. 9, pp. 1550–1563.

    MathSciNet  MATH  Google Scholar 

  11. Lomov, I.S., On the Basis Property of Systems of Irregular Root Vectors of Higher-Order Differential Operators, Differ. Uravn., 1993, vol. 29, no. 1, pp. 74–86.

    MathSciNet  MATH  Google Scholar 

  12. Afonin, S.V. and Lomov, I.S., On the Convergence of Biorthogonal Series Associated with Odd-Order Differential Operators with Nonsmooth Coefficients, Dokl. Akad. Nauk, 2010, vol. 431, no. 2, pp. 151–153.

    MathSciNet  Google Scholar 

  13. Budaev, V.D., Criteria for the Bessel Property and the Riesz Basis Property of Systems of Root Functions of Differential Operators, Differ. Uravn., 1991, vol. 27, no. 12, pp. 2033–2044.

    MathSciNet  MATH  Google Scholar 

  14. Gomilko, A.M. and Radzievskii, G.V., Equiconvergence of Series in Eigenfunctions of Ordinary Functional-Differential Operators, Dokl. Akad. Nauk, 1991, vol. 316, no. 2, pp. 265–270.

    MathSciNet  Google Scholar 

  15. Lomov, I.S., Dependence of Estimates of the Rate of Local Convergence of Spectral Expansions on the Distance from an Interior Compact Set to the Boundary, Differ. Uravn., 2010, vol. 46, no. 10, pp. 1409–1420.

    MathSciNet  Google Scholar 

  16. Sadovnichaya, I.V., Equiconvergence in Sobolev and Hölder Spaces of Expansions in Eigenfunctions of Sturm-Liouville Operators with Distribution Potentials, Dokl. Akad. Nauk, 2011, vol. 437, no. 2, pp. 162–163.

    MathSciNet  Google Scholar 

  17. Lomov, I.S., On the Convergence Rate of Biorthogonal Expansions of Functions, Differ. Uravn., 1996, vol. 32, no. 12, pp. 1618–1629.

    MathSciNet  Google Scholar 

  18. Lomov, I.S., The Generalized Bessel Inequality for Ordinary Differential Operators with Nonsmooth Coefficients and a Generalization of the Riesz Theorem, Differ. Uravn., 2000, vol. 36, no. 12, pp. 1621–1630.

    MathSciNet  Google Scholar 

  19. Lomov, I.S., Integral Representations of a Partial Sum of a Biorthogonal Series for Higher-Order Differential Operators, Differ. Uravn., 2003, vol. 39, no. 5, pp. 602–611.

    MathSciNet  Google Scholar 

  20. Lomov, I.S. and Markov, A.S., Estimates for the Local Convergence Rate of Spectral Expansions of Even-Order Differential Operators, Differ. Uravn., 2013, vol. 49, no. 5, pp. 557–563.

    MathSciNet  Google Scholar 

  21. Il’in, V.I., Izbrannye trudy (Selected Papers), Moscow, 2008, vol. 2.

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to I. S. Lomov.

Additional information

Original Russian Text © I.S. Lomov, 2014, published in Differentsial’nye Uravneniya, 2014, Vol. 50, No. 8, pp. 1077–1086.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Lomov, I.S. Loaded differential operators: Convergence of spectral expansions. Diff Equat 50, 1070–1079 (2014). https://doi.org/10.1134/S0012266114080060

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S0012266114080060

Keywords

Navigation