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On A-Self-Adjoint, A-Unitary Operators and Quasiaffinities

Received: 8 August 2016    Accepted: 18 August 2016    Published: 7 September 2016
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Abstract

In this paper, we investigate properties of A-self-adjoint operators and other relations on Hilbert spaces. In this context, A is a self-adjoint and an invertible operator. More results on operator equivalences including similarity, unitary and metric equivalences are discussed. We also investigate conditions under which these classes of operators are self- adjoint and unitary. We finally locate their spectra.

Published in Mathematics and Computer Science (Volume 1, Issue 3)
DOI 10.11648/j.mcs.20160103.14
Page(s) 56-60
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

A-Self-Adjoint, A-Unitary, Hilbert Space, Metric Equivalence, Quasiaffinities

References
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[3] Kubrusly C. S., Hilbert Space Operators, Birkha ̈users, Basel, Boston, 2003.
[4] Lins B, Meade P, Mehl C and Rodman L. Normal Matrices and Polar decompositions in infinite Inner Products. Linear and Multilinear algebra, 49: 45-89, 2001.
[5] Mehl C. and Rodman L. Classes of Normal Matrices in infinite Inner Products. Linear algebra Appl, 336: 71-98, 2001.
[6] Mostafazadeh A., Pseudo-Hermiticity versus PT-symmetry, III, Equivalance of pseudo-Hermiticity and the presence of antilinear symmetries, J. Math. Phys. 43 (8) (2002), 3944-3951.
[7] Nzimbi B. M, Pokhariyal G. P and Moindi S. K, A note on A-self-adjoint and A-Skew adjoint Operators, Pioneer Journal of Mathematics and Mathematical sciences, (2013), 1-36.
[8] Nzimbi B. M, Pokhariyal G. P and Moindi S. K, A note on Metric Equivalence of Some Operators, Far East Journal of Mathematical sciences, Vol 75, No. 2 (2013), 301-318.
[9] Nzimbi B. M., Khalagai J. M. and Pokhariyal G. P., A note on similarity, almost similarity and equivalence of operators, Far East J. Math. Sci. (FMJS) 28 (2) (2008), 305-317.
[10] Nzimbi B. M, Luketero S. W, Sitati I. N, Musundi S. W and Mwenda E, On Almost Similarity and Metric Equivalence of Operators, Accepted to be published by Pioneer Journal of Mathematics and Mathematical sciences(June 14,2016).
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[16] Tucanak M and Weiss G, Observation and Control for Operator Semi groups Birkhauser, Verlag, Basel, 2009.
[17] Virtanen J. A: Operator Theory Fall 2007.
[18] Yeung Y. H, Li C. K and L. Rodman, on H-unitary and Block Toeplitz H-normal operators, H-unitary and Lorentz matrices: A review, Preprint.
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  • APA Style

    Isaiah N. Sitati. (2016). On A-Self-Adjoint, A-Unitary Operators and Quasiaffinities. Mathematics and Computer Science, 1(3), 56-60. https://doi.org/10.11648/j.mcs.20160103.14

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    ACS Style

    Isaiah N. Sitati. On A-Self-Adjoint, A-Unitary Operators and Quasiaffinities. Math. Comput. Sci. 2016, 1(3), 56-60. doi: 10.11648/j.mcs.20160103.14

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    AMA Style

    Isaiah N. Sitati. On A-Self-Adjoint, A-Unitary Operators and Quasiaffinities. Math Comput Sci. 2016;1(3):56-60. doi: 10.11648/j.mcs.20160103.14

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  • @article{10.11648/j.mcs.20160103.14,
      author = {Isaiah N. Sitati},
      title = {On A-Self-Adjoint, A-Unitary Operators and Quasiaffinities},
      journal = {Mathematics and Computer Science},
      volume = {1},
      number = {3},
      pages = {56-60},
      doi = {10.11648/j.mcs.20160103.14},
      url = {https://doi.org/10.11648/j.mcs.20160103.14},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.mcs.20160103.14},
      abstract = {In this paper, we investigate properties of A-self-adjoint operators and other relations on Hilbert spaces. In this context, A is a self-adjoint and an invertible operator. More results on operator equivalences including similarity, unitary and metric equivalences are discussed. We also investigate conditions under which these classes of operators are self- adjoint and unitary. We finally locate their spectra.},
     year = {2016}
    }
    

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Author Information
  • School of Mathematics, College of Biological and Physical Sciences, University of Nairobi, Nairobi, Kenya

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