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arXiv · 1005.1156

A new computational approach to ideal theory in number fields

Jordi Guardia·Jesus Montes·Enric Nart
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Abstract

Let $K$ be the number field determined by a monic irreducible polynomial $f(x)$ with integer coefficients. In previous papers we parameterized the prime ideals of $K$ in terms of certain invariants attached to Newton polygons of higher order of the defining equation $f(x)$. In this paper we show how to carry out the basic operations on fractional ideals of $K$ in terms of these constructive representations of the prime ideals. From a computational perspective, these results facilitate the manipulation of fractional ideals of $K$ avoiding two heavy tasks: the construction of the maximal order of $K$ and the factorization of the discriminant of $f(x)$. The main computational ingredient is Montes algorithm, which is an extremely fast procedure to construct the prime ideals.

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Jordi Guardia, Jesus Montes, Enric Nart. 2010-07-15. A new computational approach to ideal theory in number fields. https://arxiv.org/abs/1005.1156

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