Classification of almost quarter-pinched manifolds

Petersen, Peter; Tao, Terence

doi:10.1090/S0002-9939-09-09802-5

Classification of almost quarter-pinched manifolds
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by Peter Petersen and Terence Tao PDF

Proc. Amer. Math. Soc. 137 (2009), 2437-2440 Request permission

Abstract:

We show that if a simply connected manifold is almost quarter-pinched, then it is diffeomorphic to a CROSS or a sphere.

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