Orthogonality-preserving, C*-conformal and conformal module mappings on Hilbert C*-modules
Abstract
We investigate orthonormality-preserving, C*-conformal and conformal module mappings on Hilbert C*-modules to obtain their general structure. Orthogonality-preserving bounded module maps T act as a multiplication by an element \lambda of the center of the multiplier algebra of the C*-algebra of coefficients combined with an isometric module operator as long as some polar decomposition conditions for the specific element \lambda are fulfilled inside that multiplier algebra. Generally, T always fulfils the equality for any elements x,y of the Hilbert C*-module. At the contrary, C*-conformal and conformal bounded C*-linear mappings are shown to be only the positive real multiples of isometric module operators.
Keywords
Cite
@article{arxiv.0907.2983,
title = {Orthogonality-preserving, C*-conformal and conformal module mappings on Hilbert C*-modules},
author = {Michael Frank and Alexander S. Mishchenko and Alexander A. Pavlov},
journal= {arXiv preprint arXiv:0907.2983},
year = {2025}
}
Comments
13 pages / Thm. 1.3, second paragraph of proof - corrected, minor changes of formulations in the text, references updated