Skip to main content
Log in

Demicompactness Properties for Uniformly Continuous Cosine Families

  • Published:
Mediterranean Journal of Mathematics Aims and scope Submit manuscript

Abstract

In this paper, we establish some properties for a uniformly continuous cosine family \((C(t))_{t\in \mathbb {R}}\) which has the property that C(t) is demicompact for some (resp. every) \(t>0\). More precisely, we prove that this property is equivalent to the demicompactness of \(I-A\) where A is the infinitesimal generator of the uniformly continuous cosine family \((C(t))_{t\in \mathbb {R}}\). The obtained result is used to study the spectral inclusion for a uniformly continuous cosine family for an upper semi-Fredholm spectrum. In addition, we give some perturbation results on demicompactness.

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. Aiena, P., Aponte, E., Guillen, J.R.: A strong variant of Weyl’s theorem. Syphax J. Math.: Nonlinear. Anal. Oper. Syst. 1, 36–51 (2021)

    Google Scholar 

  2. Akashi, W.Y.: On the perturbation theory for Fredholm operators. Osaka J. Math. 21, 603–612 (1984)

    MathSciNet  MATH  Google Scholar 

  3. Babesku, G.: Regularity and uniform continuity properties of cosine and sine class of operators. Lucr. Semin. Math. Fis. Inst. Politehn. Timisoara, pp. 47–50 (1983)

  4. Benkhaled, H., Elleuch, A., Jeribi, A.: Demicompactness results for strongly continuous semigroups, generators and resolvents. Mediterr. J. Math. 15 (2018)

  5. Chaker, W., Jeribi, A., Krichen, B.: Demicompact linear operators, essential spectrum and some perturbation results. Math. Nachr. 288, 1476–1486 (2015)

    Article  MathSciNet  Google Scholar 

  6. Cioranescu, I., Lizama, C.: Spectral properties of cosine operator functions. Aeq. Math. 36(1), 80–98 (1988)

    Article  MathSciNet  Google Scholar 

  7. Fattorini, H.O.: Second Order Linear Differential Equations in Banach Spaces. North-Holland, Amsterdam (1985)

    MATH  Google Scholar 

  8. Feki, I., Jeribi, A., Sfaxi, R.: Nagy’s perturbation of a non-selfadjoint operator and application to a Gribov operator in Bargmann space. Syphax J. Math. Nonlinear. Anal. Oper. Syst. 1, 1–35 (2021)

  9. Hille, E., Phillips, R. S.: Functional Analysis and Semigroups. Amer. Math. Soc. Coll. Publ. 31, Amer. Math. Soc. (1957)

  10. Jeribi, A.: Spectral Theory and Applications of Linear Operators and Block Operator Matrices. Springer, New York (2015)

  11. Jeribi, A.: Linear Operators and Their Essential Pseudospectra. CRC Press, Boca Raton (2018)

    Book  Google Scholar 

  12. Jeribi, A.: Perturbation Theory for Linear Operators: Denseness and Bases with Applications. Springer, Singapore (2021)

    Book  Google Scholar 

  13. Jeribi, A., Krichen, B., Salhi, M.: Characterization of relatively demicompact operators by means of measures of noncompactness. J. Korean Math. Soc. 55, 877–895 (2018)

    MathSciNet  MATH  Google Scholar 

  14. Lizama, C.: On the spectrum of cosine operator functions. Int. Equ. Oper. Theory 12, 713–724 (1989)

    Article  MathSciNet  Google Scholar 

  15. Lutz, D.: Strongly continuous operator cosine functions. Funct. Anal. Lect. Notes Math. 948, 73–97 (1982)

    Article  MathSciNet  Google Scholar 

  16. Nagy, B.: On cosine operator functions in Banach spaces. Acta Sci. Math. Szeged 36, 281–290 (1974)

    MathSciNet  MATH  Google Scholar 

  17. Petryshyn, W.V.: Construction of fixed points of demicompact mappings in Hilbert space. J. Math. Anal. Appl. 14, 276–284 (1966)

    Article  MathSciNet  Google Scholar 

  18. Petryshyn, W.V.: Remarks on condensing and k-set-contractive mappings. J. Math. Anal. Appl. 39, 717–741 (1972)

    Article  MathSciNet  Google Scholar 

  19. Sova, M.: Cosine operator functions. Rozprawy Matematyczne 49, 1–47 (1966)

    MathSciNet  MATH  Google Scholar 

  20. Travis, C.C., Webb, G.F.: Compactness, regularity and uniform continuity properties of strongly continuous cosine families. Houston J. Math. 3(4), 555–567 (1977)

    MathSciNet  MATH  Google Scholar 

  21. Travis, C.C., Webb, G.F.: Cosine families and abstract non-linear second order differential equations. Acta Math. Acad. Sci. Hungar. 32, 75–96 (1978)

    Article  MathSciNet  Google Scholar 

  22. Travis, C.C., Webb, G.F.: Perturbation of strongly continuous cosine family generators. Colloq. Math. 45, 277–285 (1981)

    Article  MathSciNet  Google Scholar 

  23. Williams, V.: Closed Fredholm and Semi-Fredholm Operators, Essential Spectra and Perturbations. J. Funct. Anal. 20, 1–25 (1975)

    Article  MathSciNet  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Asrar Elleuch.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Benkhaled, H., Elleuch, A. & Jeribi, A. Demicompactness Properties for Uniformly Continuous Cosine Families. Mediterr. J. Math. 19, 157 (2022). https://doi.org/10.1007/s00009-022-02083-6

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s00009-022-02083-6

Keywords

Mathematics Subject Classification

Navigation