Kida's theorem for a class of nonnormal extensions

Authors:
Robert Gold and Manohar Madan

Journal:
Proc. Amer. Math. Soc. **104** (1988), 55-60

MSC:
Primary 11R23

DOI:
https://doi.org/10.1090/S0002-9939-1988-0958043-X

MathSciNet review:
958043

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Abstract: Let be -fields of *CM*-type such that is an extension of degree . Let , the normal closure of , be such that has a normal subgroup of order . Denote the fixed field of this group by . We prove a Kida type formula which describes the minus part of the Iwasawa lambda invariant of in terms of the lambda invariants of and .

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DOI:
https://doi.org/10.1090/S0002-9939-1988-0958043-X

Article copyright:
© Copyright 1988
American Mathematical Society