Orthogonal sums in Kreĭn spaces

Rovnyak, James

doi:10.1090/proc/14718

Orthogonal sums in Kreĭn spaces
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Proc. Amer. Math. Soc. 149 (2021), 1999-2010 Request permission

Abstract:

Infinite orthogonal families of regular subspaces of a Kreĭn space exhibit a wide range of behavior. An elementary method is used to show that conditions on sums of projections produce behavior similar to that of orthogonal closed subspaces of a Hilbert space.

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