Planar growth generates scale free networks

Garvin Haslett; Seth Bullock; Markus Brede

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arXiv · 1602.03774

Planar growth generates scale free networks

Garvin Haslett·Seth Bullock·Markus Brede

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Abstract

In this paper we introduce a model of spatial network growth in which nodes are placed at randomly selected locations on a unit square in $\mathbb{R}^2$, forming new connections to old nodes subject to the constraint that edges do not cross. The resulting network has a power law degree distribution, high clustering and the small world property. We argue that these characteristics are a consequence of the two defining features of the network formation procedure; growth and planarity conservation. We demonstrate that the model can be understood as a variant of random Apollonian growth and further propose a one parameter family of models with the Random Apollonian Network and the Deterministic Apollonian Network as extreme cases and our model as a midpoint between them. We then relax the planarity constraint by allowing edge crossings with some probability and find a smooth crossover from power law to exponential degree distributions when this probability is increased.

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Garvin Haslett, Seth Bullock, Markus Brede. 2016-02-11. Planar growth generates scale free networks. https://arxiv.org/abs/1602.03774

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