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Triviality of the ℓ-class groups in $\mathbb{Z}_{p}$-extensions of $\mathbb{Q}(\sqrt{-1})$ for split primes p ≡ 1 modulo 4

Published online by Cambridge University Press:  12 May 2014

JACK LAMPLUGH*
Affiliation:
Department of Pure Mathematics and Mathematical Statistics, University of Cambridge, Cambridge, CB3 0WA. e-mail: J.Lamplugh@dpmms.cam.ac.uk

Abstract

In this paper we study the class numbers in the finite layers of certain non-cyclotomic $\mathbb{Z}$p-extensions of the imaginary quadratic field $\mathbb{Q}(\sqrt{-1})$, for all primes p ≡ 1 modulo 4. By studying the Mahler measure of elliptic units, we are able to show that there are only finitely many primes ℓ congruent to a primitive root modulo p2 that divide any of the class numbers in the $\mathbb{Z}$p-extension.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2014 

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