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A remark on the spectrum of the analytic generator

P. M. Sołtan
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Abstract

It is shown that although the spectrum of the analytic generator of a one--parameter group of isometries of a Banach space may be equal to the whole complex plane, a simple operation of ampliating the analytic generator onto its graph locates its spectrum in the positive halfline.

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P. M. Sołtan. 2006-04-28. A remark on the spectrum of the analytic generator. https://doi.org/10.1016/s0034-4877(01)80098-7

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