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Characteristic classes of Galois representations

Published online by Cambridge University Press:  24 October 2008

A. Kozlowski
Affiliation:
Department of Mathematics, Wayne State University, Detroit, MI 48202, U.S.A.

Extract

Let K be a field with char if K≠2 and let Ks denote the separable closure of K and GK the Galois group of the extension Ks/K. If KL is a finite extension and ρ:GLOr(R) a (continuous) real representation of GL we have a map ρ:BGLBO which is used to define Stiefel–Whitney classes wi(ρ) = ρ*(wi). In general if f is any element of H*(BO; ℤ/2) we denote by f(ρ) the characteristic class ρ*(f). Now let

be a genus (see e.g. [9]), for example the total Stiefel–Whitney class w = 1+w1+w2 + … Let KL and ρ be as above and let denote the multiplicative transfer (see e.g. [3, 5, 2, 14, 15]). Our principal result is a generalization of theorem 1 of [3]

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1990

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References

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