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arXiv · 1111.2734

An infinite-dimensional generalization of Zenger's lemma

Roman Drnovšek
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Abstract

We prove an infinite-dimensional generalization of Zenger's lemma that was used in the proof of the fact that the convex hull of the point spectrum of a linear operator is contained in its numerical range. Two relevant examples are given, and possible application in the Arrow-Debreu model is also discussed.

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Roman Drnovšek. 2011-11-11. An infinite-dimensional generalization of Zenger's lemma. https://doi.org/10.1016/j.jmaa.2011.11.018

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