# 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} }

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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