English

The polar decomposition for adjointable operators on Hilbert $C^*$-modules and $n$-centered operators

Operator Algebras 2018-07-16 v4 Functional Analysis

Abstract

Let nn be any natural number. The nn-centered operator is introduced for adjointable operators on Hilbert CC^*-modules. Based on the characterizations of the polar decomposition for the product of two adjointable operators, nn-centered operators, centered operators as well as binormal operators are clarified, and some results known for the Hilbert space operators are improved. It is proved that for an adjointable operator TT, if TT is Moore-Penrose invertible and is nn-centered, then its Moore-Penrose inverse is also nn-centered. A Hilbert space operator TT is constructed such that TT is nn-centered, whereas it fails to be (n+1)(n+1)-centered.

Keywords

Cite

@article{arxiv.1806.06141,
  title  = {The polar decomposition for adjointable operators on Hilbert $C^*$-modules and $n$-centered operators},
  author = {Na Liu and Wei Luo and Qingxiang Xu},
  journal= {arXiv preprint arXiv:1806.06141},
  year   = {2018}
}

Comments

The first version has been expanded and re-organized. The series will be divided into several parts. The first part [arXiv:1807.01598v2] is accepted for publication in Advances in Operator Theory. This is the second part. Some citation labels of Ref.[15] have been changed

R2 v1 2026-06-23T02:31:46.193Z