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A Generalization of a Theorem of Swan with Applications to Iwasawa Theory

Published online by Cambridge University Press:  16 November 2018

Andreas Nickel*
Affiliation:
Universität Duisburg-Essen, Fakultät für Mathematik, Thea-Leymann-Str. 9, 45127 Essen, Germany Email: [email protected]://www.uni-due.de/∼hm0251/english.html

Abstract

Let $p$ be a prime and let $G$ be a finite group. By a celebrated theorem of Swan, two finitely generated projective $\mathbb{Z}_{p}[G]$-modules $P$ and $P^{\prime }$ are isomorphic if and only if $\mathbb{Q}_{p}\otimes _{\mathbb{Z}_{p}}P$ and $\mathbb{Q}_{p}\otimes _{\mathbb{Z}_{p}}P^{\prime }$ are isomorphic as $\mathbb{Q}_{p}[G]$-modules. We prove an Iwasawa-theoretic analogue of this result and apply this to the Iwasawa theory of local and global fields. We thereby determine the structure of natural Iwasawa modules up to (pseudo-)isomorphism.

Type
Article
Copyright
© Canadian Mathematical Society 2018

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Footnotes

The author acknowledges financial support provided by the Deutsche Forschungsgemeinschaft (DFG) within the Heisenberg programme (No. NI 1230/3-1).

References

Ardakov, K. and Brown, K. A., Ring-theoretic properties of Iwasawa algebras: a survey. Doc. Math. (2006), Extra Vol., 7–33.Google Scholar
Ardakov, K. and Wadsley, S. J., On the Cartan map for crossed products and Hopf-Galois extensions. Algebr. Represent. Theory 13(2010), 3341.Google Scholar
Curtis, C. W. and Reiner, I., Methods of representation theory. Vol. I. Pure and Applied Mathematics. John Wiley & Sons, New York, 1981.Google Scholar
Curtis, C. W. and Reiner, I., Methods of representation theory. Vol. II. Pure and Applied Mathematics. John Wiley & Sons, New York, 1987.Google Scholar
Hattori, A., Rank element of a projective module. Nagoya Math. J. 25(1965), 113120.Google Scholar
Jannsen, U., Iwasawa modules up to isomorphism. In: Algebraic number theory. Adv. Stud. Pure Math., 17. Academic Press, Boston, MA, pp. 171207.Google Scholar
McConnell, J. C. and Robson, J. C., Noncommutative Noetherian rings. Revised edition., Graduate Studies in Mathematics, 30. American Mathematical Society, Providence, RI, 2001.Google Scholar
Neukirch, J., Schmidt, A., and Wingberg, K., Cohomology of number fields. Second edition., Grundlehren der Mathematischen Wissenschaften, 323. Springer-Verlag, Berlin, 2008.Google Scholar
Nickel, A., An equivariant Iwasawa main conjecture for local fields. arxiv:1803.05743.Google Scholar
Ritter, J. and Weiss, A., Toward equivariant Iwasawa theory. Manuscripta Math. 109(2002), 131146.Google Scholar
Serre, J.-P., Linear representations of finite groups. Graduate Texts in Mathematics, 42. Springer-Verlag, New York, 1977.Google Scholar
Swan, R. G., Induced representations and projective modules. Ann. of Math. (2) 71(1960), 552578.Google Scholar
Swan, R. G., Algebraic K-theory. Lecture Notes in Mathematics, 76. Springer-Verlag, Berlin, 1968.Google Scholar
Witte, M., On a localisation sequence for the K-theory of skew power series rings. J. K-Theory 11(2013), 125154.Google Scholar