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Stiefel-Whitney Classes of a Symmetric Bilinear Form — A Formula of Serre

Published online by Cambridge University Press:  20 November 2018

Victor Snaith
Victor Snaith*
Affiliation:
Department of Mathematics, The University of Western OntarioLondon, Ontario, Canada N6A 5B7
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Abstract

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Let K be a field of characteristic different from two. Let L be a finite separable extension of K. If is the separable closure of K, we have a continuous homomorphism π : Ga(/K) → ∑n(n - [L : K]). We give a very short proof of Serre's formula which evaluates the Hasse-Witt invariant of a symmetric bilinear form, transferred from L, in terms of the topological Stiefel-Whitney classes of IT.

Keywords

10C0512G0555R40
Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 28 , Issue 2 , 01 June 1985 , pp. 218 - 222
Copyright
Copyright © Canadian Mathematical Society 1985

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