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Etale homotopy and sums-of-squares formulas

Published online by Cambridge University Press:  01 July 2008

DANIEL DUGGER  and
DANIEL C. ISAKSEN
DANIEL DUGGER
Affiliation:
Department of Mathematics, University of Oregon, Eugene, OR 97403, U.S.A. e-mail: [email protected]
DANIEL C. ISAKSEN
Affiliation:
Department of Mathematics, University of Oregon, Eugene, OR 97403, U.S.A. e-mail: [email protected]
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Abstract

This paper uses a relative of BP-cohomology to prove a theorem in characteristic p algebra. Specifically, we obtain some new necessary conditions for the existence of sums-of-squares formulas over fields of characteristic p>2. These conditions were previously known in characteristic zero by results of Davis. Our proof uses a generalized étale cohomology theory called étale BP2.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 145 , Issue 1 , July 2008 , pp. 1 - 25
Copyright
Copyright © Cambridge Philosophical Society 2008

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