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arXiv · 2409.02333

Admissible groups over number fields

Deependra Singh
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Abstract

Given a field K, one may ask which finite groups are Galois groups of field extensions L/K such that L is a maximal subfield of a division algebra with center K. This connection between inverse Galois theory and division algebras was first explored by Schacher in the 1960s. In this manuscript we consider this problem when K is a number field. For the case when L/K is assumed to be tamely ramified, we give a complete classification of number fields for which every solvable Sylow-metacyclic group is admissible, extending J. Sonn's result over the field of rational numbers. For the case when L/K is allowed to be wildly ramified, we give a characterization of admissible groups over several classes of number fields, and partial results in other cases.

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Deependra Singh. 2024-09-03. Admissible groups over number fields. https://arxiv.org/abs/2409.02333

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