Existence of normal elements with prescribed norms

Autorzy

Dane publikacji

  • DOI: 10.4064/aa250108-11-3

  • Tom 221

  • Zeszyt 4

  • Czasopismo: Acta Arithmetica

  • Strony: 371-386

  • Data publikacji online: 11.11.2025

Liczba wyświetleń: 0

Liczba pobrań: 0

Abstrakt

For each positive integer $n$, let $\mathbb F_{q^n}$ be the unique $n$-degree extension of the finite field $\mathbb F_q$ with $q$ elements, where $q$ is a prime power. It is known that for arbitrary $q$ and $n$, there exist elements $\beta \in \mathbb F_{q^n}$ such that the Galois conjugates $\beta , \beta ^q, \ldots , \beta ^{q^{n-1}}$ form a basis for $\mathbb F_{q^n}$ as an $\mathbb F_q$-vector space. These elements are called normal and they work as additive generators of finite fields. On the other hand, the multiplicative group $\mathbb F_{q^n}^*$ is cyclic and any generator of this group is a primitive element. Many past works have dealt with the existence of primitive and normal elements with specified properties, including the existence of primitive elements whose traces over intermediate extensions are prescribed. Inspired by the latter, we explore the existence of normal elements whose norms over intermediate extensions are prescribed. We combine combinatorial and number-theoretic ideas and obtain both asymptotic and concrete results. In particular, we completely solve the problem in the case where only one intermediate extension is considered.
Existence of normal elements with prescribed norms - Acta Arithmetica | Wydawnictwa - Instytut Matematyczny Polskiej Akademii Nauk