A generalization of Dirichlet's unit theorem

Paul Fili; Zachary Miner

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arXiv · 1210.7884

A generalization of Dirichlet's unit theorem

Paul Fili·Zachary Miner

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Abstract

We generalize Dirichlet's $S$-unit theorem from the usual group of $S$-units of a number field $K$ to the infinite rank group of all algebraic numbers having nontrivial valuations only on places lying over $S$. Specifically, we demonstrate that the group of algebraic $S$-units modulo torsion is a $\bQ$-vector space which, when normed by the Weil height, spans a hyperplane determined by the product formula, and that the elements of this vector space which are linearly independent over $\mathbb{Q}$ retain their linear independence over $\mathbb{R}$.

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Paul Fili, Zachary Miner. 2012-10-30. A generalization of Dirichlet's unit theorem. https://arxiv.org/abs/1210.7884

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