# The norm attainment problem for functions of projections

@article{Bttcher2021TheNA, title={The norm attainment problem for functions of projections}, author={Albrecht B{\"o}ttcher and Ilya M. Spitkovsky}, journal={Archiv der Mathematik}, year={2021}, pages={1-7} }

The paper is concerned with the problem of identifying the norm attaining operators in the von Neumann algebra generated by two orthogonal projections on a Hilbert space. Every skew projection on that Hilbert space is contained in such an algebra and hence the results of the paper also describe functions of skew projections and their adjoints that attain the norm.

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