Article Contents
Article Contents

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

• 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.
Mathematics Subject Classification: Primary: 35K58; Secondary: 35R60, 35B40, 60H15.

 Citation:

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