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arXiv · 1410.3231

Bounds on variation of the spectrum and spectral subspaces of a few-body Hamiltonian

Sergio Albeverio·Alexander K. Motovilov
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Abstract

We overview the recent results on the shift of the spectrum and norm bounds for variation of spectral subspaces of a Hermitian operator under an additive Hermitian perturbation. Along with the known results, we present a new subspace variation bound for the generic off-diagonal subspace perturbation problem. We also demonstrate how some of the abstract results may work for few-body Hamiltonians.

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Sergio Albeverio, Alexander K. Motovilov. 2014-10-13. Bounds on variation of the spectrum and spectral subspaces of a few-body Hamiltonian. https://arxiv.org/abs/1410.3231

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