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arXiv · 1102.5691

Positive speed of propagation in a semilinear parabolic interface model with unbounded random coefficients

Patrick W Dondl·Michael Scheutzow
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Abstract

We consider a model for the propagation of a driven interface through a random field of obstacles. The evolution equation, commonly referred to as the Quenched Edwards-Wilkinson model, is a semilinear parabolic equation with a constant driving term and random nonlinearity to model the influence of the obstacle field. For the case of isolated obstacles centered on lattice points and admitting a random strength with exponential tails, we show that the interface propagates with a finite velocity for sufficiently large driving force. The proof consists of a discretization of the evolution equation and a supermartingale estimate akin to the study of branching random walks.

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Patrick W Dondl, Michael Scheutzow. 2011-02-28. Positive speed of propagation in a semilinear parabolic interface model with unbounded random coefficients. https://arxiv.org/abs/1102.5691

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