Strong instability of standing waves for a system of nonlinear Klein-Gordon equations with quadratic interaction

Masahito Ohta

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arXiv · 2509.06583

Strong instability of standing waves for a system of nonlinear Klein-Gordon equations with quadratic interaction

Masahito Ohta

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Abstract

We consider a system of nonlinear Klein-Gordon equations with quadratic interaction in two and three space dimensions. The strong instability of standing wave solutions is studied for the system without assuming the mass resonance condition.

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Masahito Ohta. 2025-09-08. Strong instability of standing waves for a system of nonlinear Klein-Gordon equations with quadratic interaction. https://arxiv.org/abs/2509.06583

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