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arXiv · 1007.3933

Minimal Ramification in Nilpotent Extensions

Nadya Markin·Stephen V. Ullom
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Abstract

Let $G$ be a finite nilpotent group and $K$ a number field with torsion relatively prime to the order of $G$. By a sequence of central group extensions with cyclic kernel we obtain an upper bound for the minimum number of prime ideals of $K$ ramified in a Galois extension of $K$ with Galois group isomorphic to $G$. This sharpens and extends results of Geyer and Jarden and of Plans. Also we confirm Boston's conjecture on the minimum number of ramified primes for a family of central extensions by the Schur multiplicator.

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Nadya Markin, Stephen V. Ullom. 2010-07-22. Minimal Ramification in Nilpotent Extensions. https://arxiv.org/abs/1007.3933

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