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The Olami-Feder-Christensen model on a small-world topology

F. Caruso·V. Latora·A. Rapisarda·B. Tadic
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Abstract

We study the effects of the topology on the Olami-Feder-Christensen (OFC) model, an earthquake model of self-organized criticality. In particular, we consider a 2D square lattice and a random rewiring procedure with a parameter $0<p<1$ that allows to tune the interaction graph, in a continuous way, from the initial local connectivity to a random graph. The main result is that the OFC model on a small-world topology exhibits self-organized criticality deep within the non-conservative regime, contrary to what happens in the nearest-neighbors model. The probability distribution for avalanche size obeys finite size scaling, with universal critical exponents in a wide range of values of the rewiring probability $p$. The pdf's cutoff can be fitted by a stretched exponential function with the stretching exponent approaching unity within the small-world region.

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F. Caruso, V. Latora, A. Rapisarda, B. Tadic. 2005-07-27. The Olami-Feder-Christensen model on a small-world topology. https://doi.org/10.1142/9789812701558_0041

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