Random Artin groups

Goldsborough, Antoine¹ ; Vaskou, Nicolas²

¹School of Mathematics & Computer Sciences, Heriot-Watt University, Edinburgh, United Kingdom
²Department of Mathematics, University of Bristol, Bristol, United Kingdom

Algebraic and Geometric Topology, Tome 25 (2025) no. 3, pp. 1523-1544

Résumé

We introduce a new model of random Artin groups. The two variables we consider are the rank of the Artin groups and the set of permitted coefficients of their defining graphs.

The heart of our model is to control the speed at which we make that set of permitted coefficients grow relatively to the growth of the rank of the groups, as it turns out different speeds yield very different results. We describe these speeds by means of (often polynomial) functions. In this model, we show that for a large range of such functions, a random Artin group satisfies most conjectures about Artin groups asymptotically almost surely.

Our work also serves as a study of how restrictive the commonly studied families of Artin groups are, as we compute explicitly the probability that a random Artin group belongs to various families of Artin groups, such as the classes of 2-dimensional Artin groups, FC-type Artin groups, large-type Artin groups, and others.

Détail

DOI : 10.2140/agt.2025.25.1523

Keywords: geometric group theory, Artin groups, random groups

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