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arXiv · 2207.10280

Decay rates for cubic and higher order nonlinear wave equations on asymptotically flat spacetimes

Shi-Zhuo Looi
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Abstract

In this paper, we prove pointwise decay rates for cubic and higher order nonlinear wave equations, including quasilinear wave equations, on asymptotically flat and time-dependent spacetimes. We assume that the solution to the linear equation (rather than the nonlinear equation) satisfies a weaker form of the standard integrated local energy decay, or Morawetz, estimate. For nonlinearities with a total derivative structure, we prove better pointwise decay rates.

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Shi-Zhuo Looi. 2022-07-21. Decay rates for cubic and higher order nonlinear wave equations on asymptotically flat spacetimes. https://arxiv.org/abs/2207.10280

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