Bulletin of the Australian Mathematical
Society
Bull. Austral. Math. Soc.
0004-9727
ALNBAB
2005
72
3
10.wxyz/CV72P3
http://www.austms.org.au/Publ/Bulletin/V72P3/
Similarity invariant semigroups generated by
non-Fredholm operators
Iztok
Kavkler
13 February 2006
2006
2
13
407
421
723-5201-Kavkler-2005
10.wxyz/C2005V72P3p407
http://www.austms.org.au/Publ/Bulletin/V72P3/723-5201-Kavkler/
Let $A \in B(\hs )$ be a bounded non-compact
operator that is not semi-Fredholm. The similarity invariant
semigroup generated by $A$ is shown to consist of all
operators that are not semi-Fredholm and satisfy obvious
inequalities for the nullity and co-nullity.
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