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arXiv · 1703.07983

A distance formula related to a family of projections orthogonal to their symmetries

Ilya M. Spitkovsky
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Abstract

Let u be a hermitian involution, and e an orthogonal projection, acting on the same Hilbert space. We establish the exact formula, in terms of the norm of eue, for the distance from e to the set of all orthogonal projections q from the algebra generated by e,u, and such that quq=0.

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Ilya M. Spitkovsky. 2017-03-23. A distance formula related to a family of projections orthogonal to their symmetries. https://arxiv.org/abs/1703.07983

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