On the supercritical defocusing NLW outside a ball

Piero D'Ancona

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arXiv · 1912.13216

On the supercritical defocusing NLW outside a ball

Piero D'Ancona

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Abstract

We study a defocusing semilinear wave equation, with a power nonlinearity $|u|^{p-1}u$, defined outside the unit ball of $\mathbb{R}^{n}$, $n\ge3$, with Dirichlet boundary conditions. We prove that if $p>n+4$ and the initial data are nonradial perturbations of large radial data, there exists a global smooth solution. The solution is unique among energy class solutions satisfying an energy inequality. The main tools used are the Penrose transform and a pointwise decay estimate for the exterior linear wave equation perturbed with a large, time dependent potential.

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Piero D'Ancona. 2020-07-28. On the supercritical defocusing NLW outside a ball. https://arxiv.org/abs/1912.13216

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