Levy-Nearest-Neighbors Bak-Sneppen Model

R. Cafiero; P. De Los Rios; A. Valleriani; J. L. Vega

doi:10.1103/physreve.60.r1111

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arXiv · cond-mat/9906337

Levy-Nearest-Neighbors Bak-Sneppen Model

R. Cafiero·P. De Los Rios·A. Valleriani·J. L. Vega

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Abstract

We study a random neighbor version of the Bak-Sneppen model, where "nearest neighbors" are chosen according to a probability distribution decaying as a power-law of the distance from the active site, P(x) \sim |x-x_{ac }|^{-ω}. All the exponents characterizing the self-organized critical state of this model depend on the exponent ω. As ωtends to 1 we recover the usual random nearest neighbor version of the model. The pattern of results obtained for a range of values of ωis also compatible with the results of simulations of the original BS model in high dimensions. Moreover, our results suggest a critical dimension d_c=6 for the Bak-Sneppen model, in contrast with previous claims.

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R. Cafiero, P. De Los Rios, A. Valleriani, J. L. Vega. 1999-06-22. Levy-Nearest-Neighbors Bak-Sneppen Model. https://doi.org/10.1103/physreve.60.r1111

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