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arXiv · 1705.10994

Dispersion for the wave equation outside a ball and counterexamples

Oana Ivanovici·Gilles Lebeau
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Abstract

The purpose of this note is to prove dispersive estimates for the wave equation outside a ball in R^d. If d = 3, we show that the linear flow satisfies the dispersive estimates as in R^3. In higher dimensions d $\ge$ 4 we show that losses in dispersion do appear and this happens at the Poisson spot.

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Oana Ivanovici, Gilles Lebeau. 2017-05-31. Dispersion for the wave equation outside a ball and counterexamples. https://arxiv.org/abs/1705.10994

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