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Host--parasite models on graphs

Matti Peltomaki·Ville Vuorinen·Mikko Alava·Martin Rost
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Abstract

The behavior of two interacting populations, ``hosts''and ``parasites'', is investigated on Cayley trees and scale-free networks. In the former case analytical and numerical arguments elucidate a phase diagram, whose most interesting feature is the absence of a tri-critical point as a function of the two independent spreading parameters. For scale-free graphs, the parasite population can be described effectively by Susceptible-Infected-Susceptible-type dynamics in a host background. This is shown both by considering the appropriate dynamical equations and by numerical simulations on Barabási-Albert networks with the major implication that in the termodynamic limit the critical parasite spreading parameter vanishes.

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Matti Peltomaki, Ville Vuorinen, Mikko Alava, Martin Rost. 2005-08-25. Host--parasite models on graphs. https://doi.org/10.1103/physreve.72.046134

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