On quasinilpotent operators

Jung, Il; Ko, Eungil; Pearcy, Carl

doi:10.1090/S0002-9939-03-06895-3

On quasinilpotent operators
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by Il Bong Jung, Eungil Ko and Carl Pearcy PDF

Proc. Amer. Math. Soc. 131 (2003), 2121-2127 Request permission

Abstract:

In this note we modify a new technique of Enflo for producing hyperinvariant subspaces to obtain a much improved version of his “two sequences” theorem with a somewhat simpler proof. As a corollary we get a proof of the “best” theorem (due to V. Lomonosov) known about hyperinvariant subspaces for quasinilpotent operators that uses neither the Schauder-Tychonoff fixed point theorem nor the more recent techniques of Lomonosov.

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