Notes on the sin2Θ theorem

Abstract

An analogue of the Davis-Kahan sin2Θ theorem from [SIAM J. Numer. Anal. 7 (1970), 1--46] is proved under a general spectral separation condition. This extends the generic sin2θ estimates recently shown by Albeverio and Motovilov in [Complex Anal. Oper. Theory 7 (2013), 1389--1416]. The result is applied to the subspace perturbation problem to obtain a bound on the arcsine of the norm of the difference of the spectral projections associated with isolated components of the spectrum of the unperturbed and perturbed operators, respectively.

16 pages

References in corpus (1)

• On the existence of solutions to the operator Riccati equation and the tanΘtheorem

Cited by in corpus (6)

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