English

On non-surjective word maps on $\mathrm{PSL}_{2}(\mathbb{F}_{q})$

Group Theory 2020-12-03 v1 Number Theory

Abstract

Jambor--Liebeck--O'Brien showed that there exist non-proper-power word maps which are not surjective on PSL2(Fq)\mathrm{PSL}_{2}(\mathbb{F}_{q}) for infinitely many qq. This provided the first counterexamples to a conjecture of Shalev which stated that if a two-variable word is not a proper power of a non-trivial word, then the corresponding word map is surjective on PSL2(Fq)\mathrm{PSL}_2(\mathbb{F}_{q}) for all sufficiently large qq. Motivated by their work, we construct new examples of these types of non-surjective word maps. As an application, we obtain non-surjective word maps on the absolute Galois group of Q\mathbb Q.

Cite

@article{arxiv.2012.01408,
  title  = {On non-surjective word maps on $\mathrm{PSL}_{2}(\mathbb{F}_{q})$},
  author = {Arindam Biswas and Jyoti Prakash Saha},
  journal= {arXiv preprint arXiv:2012.01408},
  year   = {2020}
}
R2 v1 2026-06-23T20:40:53.400Z