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The Blaschke conjecture and great circle fibrations of spheres

Benjamin McKay
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Abstract

We construct an explicit diffeomorphism taking any fibration of a sphere by great circles into the Hopf fibration, using elementary geometry--indeed the diffeomorphism is a local (differential) invariant, algebraic in derivatives.

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Benjamin McKay. 2001-12-03. The Blaschke conjecture and great circle fibrations of spheres. https://doi.org/10.1353/ajm.2004.0039

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