We describe all surjective isometries between open subgroups of the groups of invertible elements in unital C*-algebras. As a consequence the two C*-algebras are Jordan *-isomorphic if and only if the groups of invertible elements in those C*-algebras are isometric as metric spaces.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-sm209-2-1,
author = {Osamu Hatori and Keiichi Watanabe},
title = {Isometries between groups of invertible elements in C*-algebras},
journal = {Studia Mathematica},
volume = {209},
year = {2012},
pages = {103-106},
zbl = {1260.46036},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm209-2-1}
}
Osamu Hatori; Keiichi Watanabe. Isometries between groups of invertible elements in C*-algebras. Studia Mathematica, Tome 209 (2012) pp. 103-106. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm209-2-1/