Spectra of the difference and product of projections
Author: Matjaž Omladič
Journal: Proc. Amer. Math. Soc. 99 (1987), 317-318
MSC: Primary 47A10; Secondary 47B15
MathSciNet review: 870792
Abstract: A short natural proof of the known relation between spectra of the difference and the product of two orthogonal projections is given. This proof also generalizes this result.
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