Algebraic independence and linear difference equations

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Adamczewski, Boris, Dreyfus, Thomas, Hardouin, Charlotte, Wibmer, Michael
Natura: Preprint
Pubblicazione: 2020
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866912076838993920
author Adamczewski, Boris
Dreyfus, Thomas
Hardouin, Charlotte
Wibmer, Michael
author_facet Adamczewski, Boris
Dreyfus, Thomas
Hardouin, Charlotte
Wibmer, Michael
contents We consider pairs of automorphisms $(ϕ,σ)$ acting on fields of Laurent or Puiseux series: pairs of shift operators $(ϕ\colon x\mapsto x+h_1, σ\colon x\mapsto x+h_2)$, of $q$-difference operators $(ϕ\colon x\mapsto q_1x,\ σ\colon x\mapsto q_2x)$, and of Mahler operators $(ϕ\colon x\mapsto x^{p_1},\ σ\colon x\mapsto x^{p_2})$. Given a solution $f$ to a linear $ϕ$-equation and a solution $g$ to a linear $σ$-equation, both transcendental, we show that $f$ and $g$ are algebraically independent over the field of rational functions, assuming that the corresponding parameters are sufficiently independent. As a consequence, we settle a conjecture about Mahler functions put forward by Loxton and van der Poorten in 1987. We also give an application to the algebraic independence of $q$-hypergeometric functions. Our approach provides a general strategy to study this kind of question and is based on a suitable Galois theory: the $σ$-Galois theory of linear $ϕ$-equations.
format Preprint
id arxiv_https___arxiv_org_abs_2010_09266
institution arXiv
publishDate 2020
record_format arxiv
spellingShingle Algebraic independence and linear difference equations
Adamczewski, Boris
Dreyfus, Thomas
Hardouin, Charlotte
Wibmer, Michael
Number Theory
Group Theory
12H10, 39A06, 39A10, 39A13, 39A45, 11J81
We consider pairs of automorphisms $(ϕ,σ)$ acting on fields of Laurent or Puiseux series: pairs of shift operators $(ϕ\colon x\mapsto x+h_1, σ\colon x\mapsto x+h_2)$, of $q$-difference operators $(ϕ\colon x\mapsto q_1x,\ σ\colon x\mapsto q_2x)$, and of Mahler operators $(ϕ\colon x\mapsto x^{p_1},\ σ\colon x\mapsto x^{p_2})$. Given a solution $f$ to a linear $ϕ$-equation and a solution $g$ to a linear $σ$-equation, both transcendental, we show that $f$ and $g$ are algebraically independent over the field of rational functions, assuming that the corresponding parameters are sufficiently independent. As a consequence, we settle a conjecture about Mahler functions put forward by Loxton and van der Poorten in 1987. We also give an application to the algebraic independence of $q$-hypergeometric functions. Our approach provides a general strategy to study this kind of question and is based on a suitable Galois theory: the $σ$-Galois theory of linear $ϕ$-equations.
title Algebraic independence and linear difference equations
topic Number Theory
Group Theory
12H10, 39A06, 39A10, 39A13, 39A45, 11J81
url https://arxiv.org/abs/2010.09266