Abstract
In this paper, we establish a necessary and sufficient criterion for a finite metabelian 2-group G whose abelianized \(G^{ab}\) is of type \((2, 2^m)\), with \(m\ge 2\), to be metacyclic. This criterion is based on the rank of the maximal subgroup of G which contains the three normal subgroups of G of index 4. Then, we apply this result to study the structure of the Galois group of the maximal unramified pro-2-extension of the cyclotomic \(\mathbb {Z}_2\)-extension of certain number fields. Illustration is given by some real quadratic fields.
Similar content being viewed by others
References
A. Azizi et, A. Mouhib, Sur le rang du 2-groupe de classes de \((\mathbb{Q} \sqrt{m},\sqrt{d} )\) oú m = 2 ou un premier p = 1 mod 4. Trans. Am. Math. Soc. 7, 2741–2752 (2001)
A. Azizi, A. Mouhib, Capitulation des 2- classes d’idéaux de certains corps biquadratiques dont le corps de genres diffère du 2-corps de classes de Hilbert. Pac. J. Math. 218(1), 17–36 (2005)
A. Azizi, M. Rezzougui, M. Taous, A. Zekhnini, On the Hilbert 2-class field of some quadratic number fields. Int. J. Number Theory. 15(04), 807–824 (2019)
E. Benjamin, C. Snyder, On the rank of 2- class group of the Hilbert 2-class field of some quadratic fields. Quart. J. Math 69(4), 1163–1193 (2018)
N. Blackburn, On prime-power groups with two generators. Proc. Camb. Philos. Math. Soc. 54, 327–337 (1958)
J.D. Dixon, M.P.F. du Sautoy, A. Mann, D. Segal, Analytic Pro-p Groups, 2nd edn. (Cambridge Studies in Advanced Mathematics, Cambridge, 1999)
T. Fukuda, Remarks on \(\mathbb{Z}_p\)- extension of number fields. Proc. Japan Acad. Ser. A 70, 264–266 (1994)
G. Gras, Sur les l-classes d’idéaux dans les extensions cycliques relatives de degré premier l. Ann. Inst. Fourier Grenoble 23, fasc. 3 (1973)
R. Greenberg, On the Iwasawa invariants of totally real number fields. Am. J. Math. 98, 263–284 (1976)
H. Hasse, Neue Begründung der Theorie des Normenrestsymbols. J. Reine Angew. Math. 162, 134–143 (1930)
M. Hall, The Theory of Groups (Macmillan, New York, 1959)
G.J. Janusz, Algebric Number Fields (Academic press, New-York, 1973)
F. Lemmermeyer, The development of the principal genus theorem,arXiv:Math/0207306v1
K. Miyake, Algebraic investigations of Hilbert’s Theorem 94, the principal ideal theorem and capitulation problem. Expos. Math. 7, 289–346 (1989)
Y. Mizusawa, On the maximal unramified pro-2- extension of \(\mathbb{Z}_2\)- extensions of certain real quadratic fields II. Acta Arith. 119(1), 93–107 (2005)
L. Rédei, H. Reichardt, Die Anzahl der durch 4 teilbaren Invarianten der Klassengruppe eines beliebigen quadratischen Zahlkörpers. J. Reine Angew. Math. 170, 69–74 (1933)
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Azizi, A., Rezzougui, M. & Zekhnini, A. On the maximal unramified pro-2-extension of certain cyclotomic \(\mathbb {Z}_2\)-extensions. Period Math Hung 83, 54–66 (2021). https://doi.org/10.1007/s10998-020-00362-x
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10998-020-00362-x
Keywords
- Iwasawa theory
- \(\mathbb {Z}_2\)-extension
- 2-Class field tower
- Real quadratic field
- 2-Class group
- Metacyclic and non-metacyclic 2-group