Skip to main content
Log in

Complex Symmetry of a Dense Class of Operators

  • Published:
Integral Equations and Operator Theory Aims and scope Submit manuscript

Abstract

In this paper, we develop new techniques to study complex symmetric operators. We first give an interpolation theorem related to conjugations. This result is used to give a geometric characterization for a norm-dense class of operators to be complex symmetric. Also we characterize certain complex symmetric nilpotent operators, and several illustrating examples are given.

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. Balayan L., Garcia S.R.: Unitary equivalence to a complex symmetric matrix: geometric criteria. Oper. Matrices 4(1), 53–76 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  2. Chalendar I., Fricain E., Timotin D.: On an extremal problem of Garcia and Ross. Oper. Matrices 3(4), 541–546 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  3. Cima J.A., Garcia S.R., Ross W.T., Wogen W.R.: Truncated Toeplitz operators: spatial isomorphism, unitary equivalence, and similarity. Indiana Univ. Math. J. 59(2), 595–620 (2010)

    MathSciNet  MATH  Google Scholar 

  4. Davidson K.R.: C*-Algebras by Example, Fields Institute Monographs, vol.6. American Mathematical Society, Providence (1996)

    Google Scholar 

  5. Garcia S.R.: Aluthge transforms of complex symmetric operators. Int. Equ. Oper. Theory 60(3), 357–367 (2008)

    Article  MATH  Google Scholar 

  6. Garcia, S.R., Poore, D.E.: On the closure of the complex symmetric operators: compact operators and weighted shifts. Preprint, arXiv:1106.4855v1

  7. Garcia S.R., Poore D.E., Wyse M.K.: Unitary equivalence to a complex symmetric matrix: a modulus criterion. Oper. Matrices 5(2), 273–287 (2011)

    Article  MathSciNet  MATH  Google Scholar 

  8. Garcia S.R., Putinar M.: Complex symmetric operators and applications. Trans. Am. Math. Soc. 358(3), 1285–1315 (2006) (electronic)

    Article  MathSciNet  MATH  Google Scholar 

  9. Garcia S.R., Putinar M.: Complex symmetric operators and applications II. Trans. Am. Math. Soc. 359(8), 3913–3931 (2007) (electronic)

    Article  MathSciNet  MATH  Google Scholar 

  10. Garcia S.R., Putinar M.: Interpolation and complex symmetry. Tohoku Math. J. (2) 60(3), 423–440 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  11. Garcia, S.R., Tener, J.E.: Unitary equivalence of a matrix to its transpose. J. Oper. Theory (to appear)

  12. Garcia S.R., Wogen W.R.: Complex symmetric partial isometries. J. Funct. Anal. 257(4), 1251–1260 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  13. Garcia S.R., Wogen W.R.: Some new classes of complex symmetric operators. Trans. Am. Math. Soc. 362(11), 6065–6077 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  14. Gilbreath T.M., Wogen W.R.: Remarks on the structure of complex symmetric operators. Int. Equ. Oper. Theory 59(4), 585–590 (2007)

    Article  MathSciNet  MATH  Google Scholar 

  15. Herrero, D.A.: Approximation of Hilbert Space Operators, vol. 1, 2nd edn. Pitman Research Notes in Mathematics Series, vol. 224. Longman Scientific and Technical, Harlow (1989)

  16. Ji Y.Q.: Quasitriangular + small compact = strongly irreducible. Trans. Am. Math. Soc. 351(11), 4657–4673 (1999)

    Article  MATH  Google Scholar 

  17. Li, C.G., Zhu, S., Zhou, T.T.: Foguel operators with complex symmetry (submitted)

  18. Sarason D.: Algebraic properties of truncated Toeplitz operators. Oper. Matrices 1(4), 491–526 (2007)

    Article  MathSciNet  MATH  Google Scholar 

  19. Zhu S., Li C.G., Ji Y.Q.: The class of complex symmetric operators is not norm closed. Proc. Am. Math. Soc. 140(5), 1705–1708 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  20. Zhu S., Li C.G.: Complex symmetric weighted shifts. Trans. Am. Math. Soc. (to appear)

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Sen Zhu.

Additional information

This work was supported by NNSF of China (11101177, 11026038, 10971079), China Postdoctoral Science Foundation (2011M500064) and the Basic Research Foundation of Jilin University (201001001, 201103194).

Rights and permissions

Reprints and permissions

About this article

Cite this article

Zhu, S., Li, C.G. Complex Symmetry of a Dense Class of Operators. Integr. Equ. Oper. Theory 73, 255–272 (2012). https://doi.org/10.1007/s00020-012-1957-9

Download citation

  • Received:

  • Revised:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00020-012-1957-9

Mathematics Subject Classification (2000)

Keywords

Navigation