# Unitary similarity of projectors

```@article{Dokovic1991UnitarySO,
title={Unitary similarity of projectors},
author={Dragomir Z. Dokovic},
journal={aequationes mathematicae},
year={1991},
volume={42},
pages={220-224}
}```
• D. Dokovic
• Published 1 August 1991
• Mathematics
• aequationes mathematicae
SummaryWe deal with linear operators acting in a finite dimensional complex Hilbert space. We show that there exists a simple canonical form for projectors (not necessarily orthogonal) under unitary similarity. As a consequence we obtain a simple test for unitary similarity of projectors. IfP is a projector we show thatP andP* are unitarily similar. We also determine the isomorphism type of the algebra generated by the projectorsP andP*.
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## References

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