Speed of pulled fronts with a cutoff.
We study the effect of a small cutoff epsilon 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, 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 different variables which makes it more suitable for applications.
Benguria
R D
RD
Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago, Chile.
Depassier
M C
MC