Abstract
In this paper, we investigate the stability of regular, semi-Fredholm, finite essential ascent and finite essential descent linear relations under small and commuting finite rank perturbations as well as the behavior of the nullity, the defect and the index under such perturbations.
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Acknowledgements
The work of Teresa Álvarez was supported by Micinn (Spain). Grant MTM 2013-45643.
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Chafai, E., Álvarez, T. Finite Rank and Small Perturbations of Linear Relations. Mediterr. J. Math. 15, 202 (2018). https://doi.org/10.1007/s00009-018-1247-0
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DOI: https://doi.org/10.1007/s00009-018-1247-0