Skip to main content
Log in

On the reduction of the normal Hankel problem to two particular cases

  • Published:
Mathematical Notes Aims and scope Submit manuscript

Abstract

The normal Hankel problem (NHP) is to describe complex matrices that are normal and Hankel at the same time. The available results related to the NHP can be combined into two groups. On the one hand, there are several known classes of normal Hankel matrices. On the other hand, the matrix classes that may contain normal Hankel matrices not belonging to the known classes were shown to admit a parametrization by real 2 × 2 matrices with determinant 1. We solve the NHP for the cases where the characteristic matrix W of the given class has: (a) complex conjugate eigenvalues; (b) distinct real eigenvalues. To obtain a complete solution of the NHP, it remains to analyze two situations: (1) W is the Jordan block of order two for the eigenvalue 1; (2) W is the Jordan block of order two for −1.

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. Kh. D. Ikramov, “On a description of normal Hankel matrices,” Fundam. Prikl. Mat. 3(3), 809–819 (1997).

    MATH  MathSciNet  Google Scholar 

  2. Kh. D. Ikramov and V. N. Chugunov, “On a new class of normal Hankel matrices,” Vestnik Moskov. Univ. Ser. XV Vychisl. Mat. Kibernet. No. 1, 10–13 (2007) [Moscow Univ. Comput. Math. Cybernet. 31 (1), 8–10 (2007)].

  3. Kh. D. Ikramov and V. N. Chugunov, “On normal Hankel matrices,” Zap. Nauchn. Sem. POMI 346, 63–80 (2007) [J.Math. Sci (New York) 150 (2), 1951–1960 (2008)].

    Google Scholar 

  4. Kh. D. Ikramov and V. N. Chugunov, “On normal Hankel matrices of low orders,” Mat. Zametki 84(2), 207–218 (2008) [Math. Notes 84 (1–2), 197–206 (2008)].

    MathSciNet  Google Scholar 

  5. V. N. Chugunov and Kh. D. Ikramov, “A contribution to the normal Hankel problem,” Linear Algebra Appl. 430, 2094–2101 (2009).

    Article  MATH  MathSciNet  Google Scholar 

  6. V. V. Voevodin and E. E. Tyrtyshnikov, Computational Processes with Toeplitz Matrices (Nauka, Moscow, 1987) [in Russian].

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Kh. D. Ikramov.

Additional information

Original Russian Text © Kh. D. Ikramov, V. N. Chugunov, 2009, published in Matematicheskie Zametki, 2009, Vol. 85, No. 5, pp. 702–710.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Ikramov, K.D., Chugunov, V.N. On the reduction of the normal Hankel problem to two particular cases. Math Notes 85, 674–681 (2009). https://doi.org/10.1134/S0001434609050071

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1134/S0001434609050071

Key words

Navigation