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Small-amplitude nonlinear waves on a black hole background

Mihalis Dafermos·Igor Rodnianski
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Abstract

Let G(x) be a C^0 function such that |G(x)|\le K|x|^{p} for |x|\le c, for constants K,c>0. We consider spherically symmetric solutions of \Box_gϕ=G(ϕ) where g is a Schwarzschild or more generally a Reissner-Nordstrom metric, and such that ϕand \nabla ϕare compactly supported on a complete Cauchy surface. It is proven that for p> 4, such solutions do not blow up in the domain of outer communications, provided the initial data are small. Moreover, |ϕ|\le C(\max\{v,1\})^{-1}, where v denotes an Eddington-Finkelstein advanced time coordinate.

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Mihalis Dafermos, Igor Rodnianski. 2005-03-01. Small-amplitude nonlinear waves on a black hole background. https://arxiv.org/abs/math/0503024

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