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On metabelian 2-class field towers over $\mathbb Z_2$-extensions of real quadratic fields

Published online by Cambridge University Press:  06 October 2021

Yasushi Mizusawa*
Affiliation:
Department of Mathematics, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, 466-8555, Japan

Abstract

We give a family of real quadratic fields such that the 2-class field towers over their cyclotomic $\mathbb Z_2$ -extensions have metabelian Galois groups of abelian invariants $[2,2,2]$ . We also consider the boundedness of the Galois groups in relation to Greenberg’s conjecture, and calculate their class-2 quotients with an explicit example.

Type
Article
Copyright
© Canadian Mathematical Society 2021

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