Perturbing Fredholm operators to obtain invertible operators
نویسندگان
چکیده
منابع مشابه
Notes on Fredholm operators
(2) If K ∈ B(X) is compact, then for all λ ∈ C \ {0}, K − λ1 is Fredholm with index zero. (3) The shift operator S± ∈ B(`p) for 1 ≤ p ≤ ∞ defined by (S±x)n = xn±1 is Fredholm with index ±1. (4) If X,Y are finite dimensional and T ∈ B(X,Y ), then by the Rank-Nullity Theorem, ind(T ) = dim(X)− dim(Y ). Lemma 3. Suppose E,F ⊆ X are closed subspaces with F finite dimensional. (1) The subspace E + F...
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ژورنال
عنوان ژورنال: Journal of Functional Analysis
سال: 1975
ISSN: 0022-1236
DOI: 10.1016/0022-1236(75)90051-8