Compact perturbations of Fredholm $n$-tuples
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- Proc. Amer. Math. Soc. 122 (1994), 195-198 Request permission
Abstract:
Let T be an operator on a Hilbert space. We show that the pair (T, T) can be perturbed to an invertible pair if and only if T is Fredholm of index zero. We also exhibit a large class of Fredholm n-tuples acting on a Banach space which cannot be perturbed by finite rank operators to invertible ones.References
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Additional Information
- © Copyright 1994 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 122 (1994), 195-198
- MSC: Primary 47A53; Secondary 47A13, 47A55
- DOI: https://doi.org/10.1090/S0002-9939-1994-1201803-3
- MathSciNet review: 1201803