Let H and K be complex complete indefinite inner product spaces, and ℬ(H,K) (ℬ(H) if K = H) the set of all bounded linear operators from H into K. For every T ∈ ℬ(H,K), denote by the indefinite conjugate of T. Suppose that Φ: ℬ(H) → ℬ(K) is a bijective linear map. We prove that Φ satisfies for all A, B ∈ ℬ(H) with if and only if there exist a nonzero real number c and a generalized indefinite unitary operator U ∈ ℬ(H,K) such that for all A ∈ ℬ(H).
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-sm174-2-5,
author = {Jianlian Cui and Jinchuan Hou},
title = {Linear maps preserving elements annihilated by the polynomial $XY-YX^{\dag }$
},
journal = {Studia Mathematica},
volume = {173},
year = {2006},
pages = {183-199},
zbl = {1091.47030},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm174-2-5}
}
Jianlian Cui; Jinchuan Hou. Linear maps preserving elements annihilated by the polynomial $XY-YX^{†}$
. Studia Mathematica, Tome 173 (2006) pp. 183-199. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-sm174-2-5/