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Lifting Non-topological Divisors of Zero modulo the Compact Operators

✍ Scribed by H.O. Tylli


Publisher
Elsevier Science
Year
1994
Tongue
English
Weight
967 KB
Volume
125
Category
Article
ISSN
0022-1236

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✦ Synopsis


This paper provides the first examples of non-semiFredholm operators (S) on a Banach space such that the left or right multiplication operators (R \mapsto S R) or (R \mapsto R S) define linear embeddings of the corresponding Calkin algebra into itself. For instance, if (S) is a bounded linear operator on (C(0,1)) with closed range such that (\operatorname{Ker} S \sim l^{1}), then there is a constant (c>0) with

[
\operatorname{dist}(S R, K(C(0,1))) \geqslant c \operatorname{dist}(R, K(C(0,1)))
]

for all bounded operators (R \in L(C(0,1))). Here (K(C(0,1))) stands for the compact operators on (C(0,1)). Moreover, if (S: L^{1} \rightarrow L^{1}) has closed range and (L^{1} / \operatorname{Im} S) contains no copies of (l^{1}), then there is a constant (c>0) such that