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arXiv · 1405.3052

Counterexamples to $ C^{\infty} $ well posedness for some hyperbolic operators with triple characteristics

Enrico Bernardi·Tatsuo Nishitani
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Abstract

In this paper we prove that for a class of non-effectively hyperbolic operators with smooth triple characteristics the Cauchy problem is well posed in the Gevrey 2 class, beyond the generic Gevrey class $ 3/2 $ (see e.g. \cite{Bro}). Moreover we show that this value is optimal.

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Enrico Bernardi, Tatsuo Nishitani. 2014-05-13. Counterexamples to $ C^{\infty} $ well posedness for some hyperbolic operators with triple characteristics. https://arxiv.org/abs/1405.3052

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