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arXiv · 1911.11435

Numerical groups

María Teresa Lozano·José María Montesinos-Amilibia
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Abstract

A group of matrices $G$ with entries in a number field $K$ is defined to be numerical if $G$ has a finite index subgroup of matrices whose entries are algebraic integers. It is shown that an irreducible or completely reducible subgroup of $GL(n,K)\subset GL(n,\mathbb{C})$ is numerical if and only if the traces of its elements are algebraic integers. Some examples are given.

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María Teresa Lozano, José María Montesinos-Amilibia. 2019-11-26. Numerical groups. https://arxiv.org/abs/1911.11435

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