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On the speed of pulled fronts with a cutoff

R. D. Benguria·M. C. Depassier
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Abstract

We study the effect of a small cutoff $ε$ on the velocity of a pulled front in one dimension by means of a variational principle. We obtain a lower bound on the speed dependent on the cutoff, and for which the two leading order terms correspond to the Brunet Derrida expression. To do so we cast a known variational principle for the speed of propagation of fronts in new variables which makes it more suitable for applications.

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R. D. Benguria, M. C. Depassier. 2007-02-04. On the speed of pulled fronts with a cutoff. https://doi.org/10.1103/physreve.75.051106

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