A characterization of orthogonality preserving operators

نویسندگان

  • E. Ansari-piri Department of Mathematics‎, ‎University of Guilan‎, ‎P.O‎. ‎Box 1914‎, ‎Rasht‎, ‎Iran.
  • M. Kardel Department of Mathematics, University Campus 2, University of Guilan, P.O. Box 1914, Rasht, Iran | (As a faculty member of (and supported by) Islamic Azad University, Zabol branch, Zabol, Iran. )
  • R.G. Sanati Institute of Higher Education of ACECR(Academic Center of Education and Culture Research)‎, ‎Rasht branch‎, ‎Iran.
چکیده مقاله:

‎In this paper‎, ‎we 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 $H$‎. ‎We show that any circle (centered at the origin) is the spectrum of an orthogonality preserving operator‎. ‎Also‎, ‎we prove that every compact normal operator is a strongly orthogonality preserving operator‎.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Operators Reversing Orthogonality and Characterization of Inner Product Spaces

In this short paper we answer a question posed by Chmieliński in [Adv. Oper. Theory 1 (2016), no. 1, 8–14]. Namely, we prove that among normed spaces of dimension greater than two, only inner product spaces admit nonzero linear operators which reverse the Birkhoff orthogonality.

متن کامل

Orthogonality preserving mappings on inner product C* -modules

Suppose that A is a C^*-algebra. We consider the class of A-linear mappins between two inner product A-modules such that for each two orthogonal vectors in the domain space their values are orthogonal in the target space. In this paper, we intend to determine A-linear mappings that preserve orthogonality. For this purpose, suppose that E and F are two inner product A-modules and A+ is the set o...

متن کامل

Nested Krylov Methods and Preserving the Orthogonality

SUMMARY Recently the GMRESR inner-outer iteration scheme for the solution of linear systems of equations has been proposed by Van der Vorst and Vuik. Similar methods have been proposed by Axelsson and Vassilevski 1] and Saad (FGMRES) 10]. The outer iteration is GCR, which minimizes the residual over a given set of direction vectors. The inner iteration is GMRES, which at each step computes a ne...

متن کامل

Unitary Operators Preserving Wavelets

We characterize a special class of unitary operators that preserve orthonormal wavelets. In the process we also prove that symmetric wavelet sets cover the real line.

متن کامل

gl(A) and Differential Operators Preserving Polynomials

We discuss a certain generalization of gl,,(C), and show how it is connected to polynomial differential operators that leave the polynomial space ~,~ invariant. Mathematics Subject Classifications (1991). 17B66, 17B56, 17B35.

متن کامل

Additive Maps Preserving Idempotency of Products or Jordan Products of Operators

Let $mathcal{H}$ and $mathcal{K}$ be infinite dimensional Hilbert spaces, while $mathcal{B(H)}$ and $mathcal{B(K)}$ denote the algebras of all linear bounded operators on $mathcal{H}$ and $mathcal{K}$, respectively. We characterize the forms of additive mappings from $mathcal{B(H)}$ into $mathcal{B(K)}$ that preserve the nonzero idempotency of either Jordan products of operators or usual produc...

متن کامل

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ذخیره در منابع من قبلا به منابع من ذحیره شده

{@ msg_add @}


عنوان ژورنال

دوره 43  شماره 7

صفحات  2495- 2505

تاریخ انتشار 2017-12-30

با دنبال کردن یک ژورنال هنگامی که شماره جدید این ژورنال منتشر می شود به شما از طریق ایمیل اطلاع داده می شود.

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023