Diffusive stability of oscillations in reaction-diffusion systems

Thierry Gallay; Arnd Scheel

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arXiv · 0806.4915

Diffusive stability of oscillations in reaction-diffusion systems

Thierry Gallay·Arnd Scheel

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Abstract

We study nonlinear stability of spatially homogeneous oscillations in reaction-diffusion systems. Assuming absence of unstable linear modes and linear diffusive behavior for the neutral phase, we prove that spatially localized perturbations decay algebraically with the diffusive rate t^{-n/2} in space dimension n. We also compute the leading order term in the asymptotic expansion of the solution, and show that it corresponds to a spatially localized modulation of the phase. Our approach is based on a normal form transformation in the kinetics ODE which partially decouples the phase equation, at the expense of making the whole system quasilinear. Stability is then obtained by a global fixed point argument in temporally weighted Sobolev spaces.

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Thierry Gallay, Arnd Scheel. 2008-06-30. Diffusive stability of oscillations in reaction-diffusion systems. https://arxiv.org/abs/0806.4915

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