English

Finite-state independence

Formal Languages and Automata Theory 2017-11-07 v2 Discrete Mathematics

Abstract

In this work we introduce a notion of independence based on finite-state automata: two infinite words are independent if no one helps to compress the other using one-to-one finite-state transducers with auxiliary input. We prove that, as expected, the set of independent pairs of infinite words has Lebesgue measure 1. We show that the join of two independent normal words is normal. However, the independence of two normal words is not guaranteed if we just require that their join is normal. To prove this we construct a normal word x1x2x3x_1x_2x_3\ldots where x2n=xnx_{2n}=x_n for every nn.

Cite

@article{arxiv.1611.03921,
  title  = {Finite-state independence},
  author = {Verónica Becher and Olivier Carton and Pablo Ariel Heiber},
  journal= {arXiv preprint arXiv:1611.03921},
  year   = {2017}
}
R2 v1 2026-06-22T16:50:01.726Z