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How does degree heterogeneity affect an order-disorder transition?

R. Lambiotte
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Abstract

We focus on the role played by the node degree distribution on the way collective phenomena emerge on complex networks. To address this question, we focus analytically on a typical model for cooperative behaviour, the Majority Rule, applied to dichotomous networks. The latter are composed of two kinds of nodes, each kind $i$ being characterized by a degree $k_i$. Dichotomous networks are therefore a simple instance of heterogeneous networks, especially adapted in order to reveal the effect of degree heterogeneity. Our main result are that degree heterogeneity affects the location of the order-disorder transition and that the system exhibits non-equipartition of the average opinion between the two kinds of nodes. This effect is observed in the ordered phase and in the disordered phase.

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R. Lambiotte. 2007-04-17. How does degree heterogeneity affect an order-disorder transition?. https://doi.org/10.1209/0295-5075%2F78%2F68002

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