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arXiv · 0906.2471

Coevolution of Glauber-like Ising dynamics and topology

Salvatore Mandra'·Santo Fortunato·Claudio Castellano
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Abstract

We study the coevolution of a generalized Glauber dynamics for Ising spins, with tunable threshold, and of the graph topology where the dynamics takes place. This simple coevolution dynamics generates a rich phase diagram in the space of the two parameters of the model, the threshold and the rewiring probability. The diagram displays phase transitions of different types: spin ordering, percolation, connectedness. At variance with traditional coevolution models, in which all spins of each connected component of the graph have equal value in the stationary state, we find that, for suitable choices of the parameters, the system may converge to a state in which spins of opposite sign coexist in the same component, organized in compact clusters of like-signed spins. Mean field calculations enable one to estimate some features of the phase diagram.

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Salvatore Mandra', Santo Fortunato, Claudio Castellano. 2009-06-13. Coevolution of Glauber-like Ising dynamics and topology. https://doi.org/10.1103/physreve.80.056105

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