A new hierarchy of avalanches observed in Bak-Sneppen evolution model

W. Li; X. Cai

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arXiv · cond-mat/9905239

A new hierarchy of avalanches observed in Bak-Sneppen evolution model

W. Li·X. Cai

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Abstract

A new quantity, average fitness, is introduced in Bak-Sneppen evolution model. Through this new quantity, a new hierarchy of avalanches is observed in the evolution of Bak-Sneppen model. An exact gap equation, governing the self-organization of the model, is presented. It is found that the self-organized threshold of the new quantity can be exactly obtained. Two basic exponents, avalanche distribution and avalanche dimension are given through simulations of one- and two-dimensional Bak-Sneppen models. It is suggested that this new quantity may be a good quantity in determining the emergence of criticality.

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W. Li, X. Cai. 1999-05-17. A new hierarchy of avalanches observed in Bak-Sneppen evolution model. https://arxiv.org/abs/cond-mat/9905239

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