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Spectral, and Numerical Range, Approximants

  • Philip J. Maher
Chapter

Abstract

The theory of spectral approximants presents a precise geometric way of specifying approximants. The theory was initiated by Halmos [22] and later extended to the context of \(\mathcal{C}_{p}\) by Bouldin [11] and Bhatia [8]. More recently the related concept of numerical range approximant was introduced [25].

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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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