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Journal of Mathematical Sciences

, Volume 137, Issue 3, pp 4763–4768 | Cite as

Unitary similarity of algebras generated by pairs of orthoprojectors

  • Yu. A. Al’pin
  • Kh. D. Ikramov
Article

Abstract

It is shown that the unitary similarity of two matrix algebras generated by pairs of orthoprojectors { P1, Q1} and {P2,Q2} can be verified by comparing the traces of P1, Q1, and (P1Q1)i, i = 1, 2, …, n, with those of P2, Q2, and (P2Q2)i. The conditions of the unitary similarity of two matrices with quadratic minimal polynomials presented in [A. George and Kh. D. Ikramov, Unitary similarity of matrices with quadratic minimal polynomials, Linear Algebra Appl., 349, 11–16 (2002)] are refined. Bibliography: 10 titles.

Keywords

Canonical Form Normal Family Minimal Polynomial Distinct Eigenvalue Oblique Projector 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Yu. A. Al’pin
    • 1
  • Kh. D. Ikramov
    • 2
  1. 1.Kazan’ State UniversityKazan’Russia
  2. 2.Moscow State UniversityMoscowRussia

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