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arXiv · 1112.3195

Propagation de la 2-birationalité

Claire Bourbon·Jean-François Jaulent
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Abstract

Let L/K be a 2-birational CM-extension of a totally real 2-rational number field. We characterize in terms of tame ramification totally real 2-extensions K'/K such that the compositum L'= LK' is still 2-birational. In case the 2-extensions K'/K is linearly disjoint from the cyclotomic Z2-extension Kc/K, we prove that K'/K is at most quadratic. In the other hand we construct infinite towers of such 2-extensions.

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Claire Bourbon, Jean-François Jaulent. 2011-12-14. Propagation de la 2-birationalité. https://arxiv.org/abs/1112.3195

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