English

On Word Representations and Embeddings in Complex Matrices

Formal Languages and Automata Theory 2026-04-20 v1 Discrete Mathematics Group Theory Representation Theory

Abstract

Embeddings of word structures into matrix semigroups provide a natural bridge between combinatorics on words and linear algebra. However, low-dimensional matrix semigroups impose strong structural restrictions on possible embeddings. Certain finitely generated groups admit faithful representations in SL(2, C) and other similar matrix groups. On the other hand, it is known that the product of two free semigroups on two generators cannot be embedded into the 2x2 complex matrices. In this paper we study embeddings of word structures into low-dimensional matrix semigroups over the complex numbers and develop new techniques for constructing word representations of the Euclidean Bianchi groups. These representations provide a symbolic framework and a natural first step towards analysing fundamental decision problems in 2x2 matrix semigroups.

Keywords

Cite

@article{arxiv.2604.15386,
  title  = {On Word Representations and Embeddings in Complex Matrices},
  author = {Paul C. Bell and George Kenison and Reino Niskanen and Igor Potapov and Pavel Semukhin},
  journal= {arXiv preprint arXiv:2604.15386},
  year   = {2026}
}

Comments

23 pages. Full version of conference paper accepted to DLT 2026

R2 v1 2026-07-01T12:13:20.146Z