Special Matrices (Jan 2021)

Permutative universal realizability

  • Soto Ricardo L.,
  • Julio Ana I.,
  • Alfaro Jaime H.

DOI
https://doi.org/10.1515/spma-2020-0123
Journal volume & issue
Vol. 9, no. 1
pp. 66 – 77

Abstract

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A list of complex numbers Λ is said to be realizable, if it is the spectrum of a nonnegative matrix. In this paper we provide a new sufficient condition for a given list Λ to be universally realizable (UR), that is, realizable for each possible Jordan canonical form allowed by Λ. Furthermore, the resulting matrix (that is explicity provided) is permutative, meaning that each of its rows is a permutation of the first row. In particular, we show that a real Suleĭmanova spectrum, that is, a list of real numbers having exactly one positive element, is UR by a permutative matrix.

Keywords