Special Matrices (Jul 2018)

The Diagonalizable Nonnegative Inverse Eigenvalue Problem

  • Cronin Anthony G,
  • Laffey Thomas J.

DOI
https://doi.org/10.1515/spma-2018-0023
Journal volume & issue
Vol. 6, no. 1
pp. 273 – 281

Abstract

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In this articlewe provide some lists of real numberswhich can be realized as the spectra of nonnegative diagonalizable matrices but which are not the spectra of nonnegative symmetric matrices. In particular, we examine the classical list σ = (3 + t, 3 − t, −2, −2, −2) with t ≥ 0, and show that 0 is realizable by a nonnegative diagonalizable matrix only for t ≥ 1. We also provide examples of lists which are realizable as the spectra of nonnegative matrices, but not as the spectra of nonnegative diagonalizable matrices by examining the Jordan Normal Form

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