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arXiv · 1709.01908

Opening the Maslov Box for Traveling Waves in Skew-Gradient Systems

Paul Cornwell
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Abstract

We obtain geometric insight into the stability of traveling pulses for reaction-diffusion equations with skew-gradient structure. For such systems, a Maslov index of the traveling wave can be defined and related to the eigenvalue equation for the linearization $L$ about the wave. We prove two main results about this index. First, for general skew-gradient systems, it is shown that the Maslov index gives a lower bound on the number of real, unstable eigenvalues of $L$. Second, we show how the Maslov index gives an exact count of all unstable eigenvalues for fast traveling waves in a FitzHugh-Nagumo system. The latter proof involves the Evans function and reveals a new geometric way of understanding algebraic multiplicity of eigenvalues.

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Paul Cornwell. 2017-09-06. Opening the Maslov Box for Traveling Waves in Skew-Gradient Systems. https://arxiv.org/abs/1709.01908

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