Numerical Computation of an Evans Function in the Fisher/kpp Equation
نویسندگان
چکیده
We demonstrate a geometrically inspired technique for computing an Evans function for the linearised operator about a travelling wave in the Fisher/KPP equation. We produce an Evans function which is computable through several orders of magnitude in the spectral parameter and show how such a function can naturally be extended into the continuous spectrum. We conclude with a new proof of stability of travelling waves of speed c ≥ 2 √ δ in the Fisher/KPP equation, and discuss extensions to travelling waves in higher order systems of PDEs.
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