English

Powers of posinormal operators

Functional Analysis 2022-02-22 v1

Abstract

Square of a posinormal operator is not necessarily posinormal.. But (i) powers of quasiposinormal operators are quasiposinormal and, under closed ranges assumption, powers of (ii) posinormal operators are posinormal, (iii) of operators that are both posinormal and coposinormal are posinormal and coposinormal, and (iv) of semi-Fredholm posinormal operators are posinormal.

Keywords

Cite

@article{arxiv.2202.09525,
  title  = {Powers of posinormal operators},
  author = {C. S. Kubrusly and P. C. M. Vieira and J. Zanni},
  journal= {arXiv preprint arXiv:2202.09525},
  year   = {2022}
}
R2 v1 2026-06-24T09:45:35.282Z