2025/106/3-4 (2)
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DOI: 10.5486/PMD.2025.9771
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pp. 285-299
On the explicit Galois group of $\mathbb{Q}\Big(a_{1}^{\frac{1}{m}},a_{2}^{\frac{1}{m}},\dots,a_{n}^{\frac{1}{m}},\zeta_{m}\Big)$ over $\mathbb{Q}$
Abstract:
Let $m>1$ be an integer, and $\zeta_m$ denote a primitive $m$-th root of unity. For any finite set $S= \{ a_{1}, a_{2}, \dots, a_{n} \}$ and arbitrary choice of $m$-th roots of unity $\zeta_m^{r_i}$, $0 \leq r_i < m$ for $i=1, \dots, n$, we study the density of primes $\mathbf{p}$ of $\mathbb{Q}(\zeta_m)$ such that the $m$-th power residue symbol $\left(\frac{a_i}{\mathbf{p}}\right)_m =\zeta_m^{r_i}$. We calculate the explicit structure of the Galois group $\operatorname{Gal}{\mathbb{Q}(a_1^{\frac{1}{m}}, \ldots, a_n^{\frac{1}{m}},\zeta_m)/\mathbb{Q}(\zeta_{m})}$ in terms of its action on $a_{i}^{\frac{1}{m}}$ for $1 \leq i \leq n$.
Keywords: $m$-th power residue, extensions obtained by adjoining $m$-th roots, distribution of prime ideals
Mathematics Subject Classification: 11R21, 11R18, 11R44

