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Unitary, Isometric and Partially Isometric Approximation of Positive Operators

  • Philip J. Maher
Chapter

Abstract

This chapter is about approximation of positive operators by operators that in some sense preserve size: by—in ascending order of generality—unitaries, isometries and partial isometries.

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Philip J. Maher
    • 1
  1. 1.LondonUK

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