English

Alphabets, rewriting trails and periodic representations in algebraic bases

Number Theory 2021-09-30 v3 Discrete Mathematics

Abstract

For β>1\beta > 1 a real algebraic integer ({\it the base}), the finite alphabets AZ\mathcal{A} \subset \mathbb{Z} which realize the identity Q(β)=PerA(β)\mathbb{Q}(\beta) = {\rm Per}_{\mathcal{A}}(\beta), where PerA(β){\rm Per}_{\mathcal{A}}(\beta) is the set of complex numbers which are (β,A)(\beta, \mathcal{A})-eventually periodic representations, are investigated. Comparing with the greedy algorithm, minimal and maximal alphabets are defined. The maximal alphabets are shown to be correlated to the asymptotics of the Pierce numbers of the base β\beta and Lehmer's problem. The notion of rewriting trail is introduced to construct intermediate alphabets associated with small polynomial values of the base. Consequences on the representations of neighbourhoods of the origin in Q(β)\mathbb{Q}(\beta), generalizing Schmidt's theorem related to Pisot numbers, are investigated. Applications to Galois conjugation are given for convergent sequences of bases γs:=γn,m1,,ms\gamma_s := \gamma_{n, m_1 , \ldots , m_s} such that γs1\gamma_{s}^{-1} is the unique root in (0,1)(0,1) of an almost Newman polynomial of the type 1+x+xn+xm1++xms-1+x+x^n +x^{m_1}+\ldots+ x^{m_s}, n3n \geq 3, s1s \geq 1, m1nn1m_1 - n \geq n-1, mq+1mqn1m_{q+1}-m_q \geq n-1 for all q1q \geq 1. For β>1\beta > 1 a reciprocal algebraic integer close to one, the poles of modulus <1< 1 of the dynamical zeta function of the β\beta-shift ζβ(z)\zeta_{\beta}(z) are shown, under some assumptions, to be zeroes of the minimal polynomial of β\beta.

Keywords

Cite

@article{arxiv.2012.15135,
  title  = {Alphabets, rewriting trails and periodic representations in algebraic bases},
  author = {Denys Dutykh and Jean-Louis Verger-Gaugry},
  journal= {arXiv preprint arXiv:2012.15135},
  year   = {2021}
}

Comments

17 pages, 7 figures, 29 references

R2 v1 2026-06-23T21:35:45.139Z