Simple proof of a useful pointwise estimate for the wave equation

Nikodem Szpak

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arXiv · 0708.2801

Simple proof of a useful pointwise estimate for the wave equation

Nikodem Szpak

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Abstract

We give a simple proof of a pointwise decay estimate in 3+1 dimensions stated in two versions, making advantage of a particular simplicity of inverting the spherically symmetric part of the wave operator and of the comparison theorem. We briefly explain the role of this estimate in proving decay estimates for nonlinear wave equations or wave equations with potential terms.

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Nikodem Szpak. 2007-10-09. Simple proof of a useful pointwise estimate for the wave equation. https://arxiv.org/abs/0708.2801

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