Event № 1614

We focus on a model in front propagation introduced by E. Brunet and B. Derrida [2004], in which $N$ of particles evolve on the real line. The dynamics is determined by a branching-selection mechanism, so the particles remain grouped and move like a travelling front. The model can be seen as a directed polymer in random medium or as the evolution of a population subjected to mutation and selection. We focus on the case where the noise lies in the max-domain of attraction of the Weibull extreme value distribution and show that under mild conditions the correction to the speed has universal features depending on the tail probabilities.