ORTHOGONALITY PRESERVING TRANSFORMATIONS ON THE SET OF n-DIMENSIONAL SUBSPACES OF A HILBERT SPACE
نویسنده
چکیده
We characterize bijective transformations on the set of all n-dimensional subspaces of a Hilbert space that preserve orthogonality in both directions. This extends Uhlhorn’s improvement of Wigner’s classical theorem on symmetry transformations.
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