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arXiv · 2404.12878

John's blow up examples and scattering solutions for semi-linear wave equations

Louie Bernhardt·Volker Schlue·Dongxiao Yu
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Abstract

In light of recent work of the third author, we revisit a classic example given by Fritz John of a semi-linear wave equation which exhibits finite in time blow up for all compactly supported data. We present the construction of future global solutions from asymptotic data given in arXiv:2204.12870(2022) for this specific example, and clarify the relation of this result of Yu to John's theorem. Furthermore we present a novel blow up result for finite energy solutions satisfying a sign condition due to the first author, and invoke this result to show that the constructed backwards in time solutions blow up in the past.

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Louie Bernhardt, Volker Schlue, Dongxiao Yu. 2024-04-19. John's blow up examples and scattering solutions for semi-linear wave equations. https://arxiv.org/abs/2404.12878

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