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Asymptotic Scaling of the Diffusion Coefficient of Fluctuating "Pulled" Fronts

Debabrata Panja
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Abstract

We present a (heuristic) theoretical derivation for the scaling of the diffusion coefficient $D_f$ for fluctuating ``pulled'' fronts. In agreement with earlier numerical simulations, we find that as $N\to\infty$, $D_f$ approaches zero as $1/\ln^3N$, where $N$ is the average number of particles per correlation volume in the stable phase of the front. This behaviour of $D_f$ stems from the shape fluctuations at the very tip of the front, and is independent of the microscopic model.

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Debabrata Panja. 2003-10-13. Asymptotic Scaling of the Diffusion Coefficient of Fluctuating "Pulled" Fronts. https://doi.org/10.1103/physreve.68.065202

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