Etale homotopy and sums-of-squares formulas

Daniel Dugger; Daniel C. Isaksen

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arXiv · math/0609301

Etale homotopy and sums-of-squares formulas

Daniel Dugger·Daniel C. Isaksen

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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 etale cohomology theory called etale BP2.

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Daniel Dugger, Daniel C. Isaksen. 2006-09-11. Etale homotopy and sums-of-squares formulas. https://arxiv.org/abs/math/0609301

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