@article{Zhou2025, 
author = {Kai Zhou and Zhenhua Gu and Hongfeng Wu},
title = {Orthogonality preserving transformations on complex projective spaces},
year = {2025},
journal = {AIMS Mathematics},
volume = {10},
number = {5},
pages = {11411-11434},
keywords = {H-orthogonal, unitary group, isotropic vector, orthogonality preserving, Wigner theorem},
url = {https://www.sciopen.com/article/10.3934/math.2025519},
doi = {10.3934/math.2025519},
abstract = {It is well known that transformations of              C        n   preserving the standard inner product are unitary transformations. In this paper, all bijective transformations of isotropic sets of        C        P          n       preserving    H-orthogonality in both directions, called    H-orthogonal transformations, have been determined. This is a generalization of Uhlhorn's version of Wigner's unitary-antiunitary theorem. The group of    H-orthogonal transformations on some other sets of        C        P          n       were also determined.}
}