Article Sidebar

Submitted
December 8, 2023
Published
November 30, 2023
Download
PDF
Statistic
Read Counter : 344 Download : 437

Downloads

Download data is not yet available.

Main Article Content

Abstract

The notion of semi-inner product (SIP) spaces is a generalization of inner product (IP) spaces notion by reducing the positive definite property of the product to positive semi-definite. As in IP spaces, the existence of an adjoint of a linear operator on a SIP space is guaranteed when the operator is bounded. However, in contrast, a bounded linear operator on SIP space can have more than one adjoint linear operators. In this article we give an alternative proof of those results using the generalized Riesz Representation Theorem in SIP space. Further, the description of all adjoint operators of a bounded linear operator in SIP space is identified.

Keywords

semi-inner product space adjoint bounded operator Riesz representation theorem

Article Details

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

How to Cite
Respitawulan, R., Pangestu, Q. Y. ., Kusniyanti, E., Yuliawan, F., & Astuti, P. . (2023). On The Adjoint of Bounded Operators On A Semi-Inner Product Space. Journal of the Indonesian Mathematical Society, 29(3), 311–321. https://doi.org/10.22342/jims.29.3.1598.311-321
Download Citation
Endnote/Zotero/Mendeley (RIS)
BibTeX
Crossref
Scopus
Google Scholar
Europe PMC

References

  1. Arias, M. L., Corach, G., and Gonzalez, M. C., ”Partial isometries in semi-Hilbertian spaces. Linear Algebra and its Applications”, 428(7) (2008), 1460-1475.
  2. Arias, M. L., Corach, G., and Gonzalez, M. C., ”Metric properties of projections in semiHilbertian spaces”, Integral Equations and Operator Theory, 62(1) (2008), 11-28.
  3. Ahmed, O. A. M. S., and Saddi, A., ”A-m-Isometric operators in semi-Hilbertian spaces”, Lin. Algebra and its appl., 436(10) (2012), 3930-3942.
  4. Baklouti, H., and Namouri, S., ”Closed operator in semi-Hilbertian spaces”, Lin. and Multilinear Algebra, 70(20) (2022) 5847-5858.
  5. Benali, A., and Mahmoud, S.A.O.A., ”(α, β)-A-Normal operators in semi-Hilbertian spaces”, Afrika Matematika, 30(5) (2019), 903-920.
  6. Bhunia, P., Kittaneh, F., Paul, K., and Sen, A. ”Anderson’s theorem and A-spectral radius bounds for semi-Hilbertian space operators.” Lin. Alg. and its Appl., 657 (2023), 147-162.
  7. Bovdi, V.A., Klymchuk, T., Rybalkina, T., Salima,M.A., and Sergeichuk, V.V., ”Operators on positive semi-definite inner product spaces”, Lin. Alg. and its Appl., 596 (2020),82-105.
  8. Kittaneh, F., and Zamani,A., ”A refinement of A-Buzano inequality and applications to A-numerical radius inequalities”, Lin. Alg. and its Appl., (2023).
  9. Krein, M. G., ”Compact linear operators on functional spaces with two norms”, Integral Equations and Operator Theory, 30(2) (1998), 140-162.
  10. Promislow, S. D., A first course in functional analysis, Wiley-Interscience, 2008.
  11. Saddi, A., ”A-Normal operators in Semi-Hilbertian spaces”, The Australian J. of Math. Anal. and Appl., 9(1) (2012), 1-12.
  12. Sen, J., Sain, D., and Paul, K., ”Orthogonality and norm attainment of operators in semiHilbertian space”, Ann. of Funct. Anal., 12(1) (2021), 1-12.
  13. Sen, J., and Paul, K., ”(ε, A)-approximate numerical radius orthogonality and numerical radius derivative”, Mathematica Slovaca 73(1) (2023), 147-158.
  14. Sun W., ”Generalized inverse solution for general quadratic programming”, Num. Math. J. of Chinese Univ., (1991) 94-98.
  15. Tam, T.Y and Zhang, P., Spectral decomposition of selfadjoint matrices in positive semidefinite inner product spaces and its applications, Lin. and Multilinear Algebra, 67(9)(2019),1829-1838.
  16. Zaanen, A.C., ”Normalisable transformations in Hilbert space and systems of linear integral equations”, Acta Math., 83 (1950), 197–248.
  17. Zamani, A., ”Birkhoff-James orthogonality of operators in semi-Hilbertian spaces and its applications”, Ann. of Funct. Anal., 10(3) (2019), 433-445