First-order aspects of Artin groups
Abstract
We prove several results on the model theory of Artin groups, focusing on Artin groups which are ``far from right-angled Artin groups''. The first result is that if is a class of Artin groups whose irreducible components are acylindrically hyperbolic and torsion-free, then the model theory of Artin groups of type reduces to the model theory of its irreducible components. The second result is that the problem of superstability of a given non-abelian Artin group reduces to certain dihedral parabolic subgroups of being -pure in , for certain large enough primes . The third result is that two spherical Artin groups are elementary equivalent if and only if they are isomorphic. Finally, we prove that the affine Artin groups of type , for , can be distinguished from the other simply laced affine Artin groups using existential sentences; this uses homology results of independent interest relying on the recent proof of the conjecture for affine Artin groups.
Cite
@article{arxiv.2507.21575,
title = {First-order aspects of Artin groups},
author = {Alberto Cassella and Gianluca Paolini and Giovanni Paolini},
journal= {arXiv preprint arXiv:2507.21575},
year = {2025}
}