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Absence of epidemic threshold in scale-free networks with connectivity correlations

Marian Boguna·Romualdo Pastor-Satorras·Alessandro Vespignani
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Abstract

Random scale-free networks have the peculiar property of being prone to the spreading of infections. Here we provide an exact result showing that a scale-free connectivity distribution with diverging second moment is a sufficient condition to have null epidemic threshold in unstructured networks with either assortative or dissortative mixing. Connectivity correlations result therefore ininfluential for the epidemic spreading picture in these scale-free networks. The present result is related to the divergence of the average nearest neighbors connectivity, enforced by the connectivity detailed balance condition.

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Marian Boguna, Romualdo Pastor-Satorras, Alessandro Vespignani. 2002-08-08. Absence of epidemic threshold in scale-free networks with connectivity correlations. https://doi.org/10.1103/physrevlett.90.028701

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