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arXiv · 2607.17501

Unique inversion of smooth nonlinearity in semilinear wave equations on Lorentzian manifolds

Xi Chen·Shuai Lu·Ruochong Zhang
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Abstract

We study the recovery of a smooth nonlinearity in semilinear wave equations on globally hyperbolic Lorentzian manifolds. Our approach combines higher-order linearization with distorted plane waves and Gaussian beams, using three-wave, four-wave, and m-wave interactions to recover different Taylor coefficients.

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Xi Chen, Shuai Lu, Ruochong Zhang. 2026-07-20. Unique inversion of smooth nonlinearity in semilinear wave equations on Lorentzian manifolds. https://arxiv.org/abs/2607.17501

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