A characterization of orthogonality preserving operators

Author(s):

E. Ansari-Piri , R.G. Sanati * , M. Kardel

Article Type:
Research/Original Article (دارای رتبه معتبر)
Abstract:
ýIn this paperý, ýwe characterize the class of orthogonality preserving operators on an infinite-dimensional Hilbert space H as scalar multiples of unitary operators between H and some closed subspaces of Hý. ýWe show that any circle (centered at the origin) is the spectrum of an orthogonality preserving operatorý. ýAlsoý, ýwe prove that every compact normal operator is a strongly orthogonality preserving operatorý.
Keywords:

Orthogonality preserving operators? , ?adjoint of operators? , isometry? , unitary operators?

Language:
English
Published:
Bulletin of Iranian Mathematical Society, Volume:43 Issue: 7, 2017
Pages:
2495 to 2505
https://www.magiran.com/p1850931