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arXiv · 2512.20718

Propagation Estimates for the Boson Star Equation

Sébastien Breteaux·Jérémy Faupin·Viviana Grasselli
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Abstract

We consider the boson star equation with a general two-body interaction potential $w$ and initial data $\psi_0$ in a Sobolev space. Under general assumptions on $w$, namely that $w$ decomposes as a sum of a finite, signed measure and an essentially bounded function, we prove that the (local in time) solution cannot propagate faster than the speed of light, up to a sharp exponentially small remainder term. If $w$ is short-range and $\psi_0$ is regular and small enough, we prove in addition asymptotic phase-space propagation estimates and minimal velocity estimates for the (global in time) solution, depending on the momentum of the scattering state associated to $\psi_0$.

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Sébastien Breteaux, Jérémy Faupin, Viviana Grasselli. 2025-12-23. Propagation Estimates for the Boson Star Equation. https://arxiv.org/abs/2512.20718

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