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Internal Fluctuations Effects on Fisher Waves

Esteban Moro
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Abstract

We study the diffusion-limited reaction A + A <-> A in different spatial dimensions to observe the effect of internal fluctuations on the interface between stable and unstable phases. We find that, similar to what has been observed in d=1 dimensions, internal fluctuations modify the mean-field behavior predictions for this process, which is given by Fisher's reaction-diffusion equation. In d > 1 the front displays local fluctuations perpendicular to the direction of motion which, with a proper definition of the interface, can be fully described within the Kardar-Parisi-Zhang (KPZ) universality class. This clarifies the apparent discrepancies with KPZ predictions reported recently.

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Esteban Moro. 2001-05-03. Internal Fluctuations Effects on Fisher Waves. https://doi.org/10.1103/physrevlett.87.238303

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