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arXiv · 1310.6202

Less than one implies zero

Felix Schwenninger·Hans Zwart
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Abstract

In this paper we show that from the estimate $\sup_{t \geq 0}\|C(t) - \cos(at)I\| <1$ we can conclude that $C(t)$ equals $\cos(at) I$. Here $\left(C(t)\right)_{t \geq 0}$ is a strongly continuous cosine family on a Banach space.

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Felix Schwenninger, Hans Zwart. 2013-10-23. Less than one implies zero. https://doi.org/10.4064/sm8218-12-2015

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