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arXiv · 2004.11708

The spectrum of the restriction to an invariant subspace

Dimosthenis Drivaliaris·Nikos Yannakakis
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Abstract

Let $X$ be a Banach space, $A\in B(X)$ and $M$ be an invariant subspace of $A$. We present an alternative proof that, if the spectrum of the restriction of $A$ to $M$ contains a point that is in any given hole in the spectrum of $A$, then the entire hole is in the spectrum of the restriction.

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Dimosthenis Drivaliaris, Nikos Yannakakis. 2020-04-24. The spectrum of the restriction to an invariant subspace. https://doi.org/10.7153/oam-2020-14-19

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