Generalizations of semi-Fredholm operators

Bouldin, Richard

doi:10.1090/S0002-9939-1995-1301011-2

Generalizations of semi-Fredholm operators
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Proc. Amer. Math. Soc. 123 (1995), 3757-3764 Request permission

Abstract:

On nonseparable Hilbert spaces there are multiple sets of operators that are analogous to the semi-Fredholm operators on a separable space. We develop the properties of these sets and relate those properties to some recent research. We conclude with a theorem that indicates precisely how far one can go from a given generalized semi-Fredholm operator (or generalized Fredholm operator) and retain the property of generalized semi-Fredholmness (or generalized Fredholmness).

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