Examples of Riemannian manifolds with positive curvature almost everywhere

نویسندگان

  • Peter Petersen
  • Frederick Wilhelm
چکیده

We show that the unit tangent bundle of S4 and a real cohomology CP 3 admit Riemannian metrics with positive sectional curvature almost everywhere. These are the only examples so far with positive curvature almost everywhere that are not also known to admit positive curvature. AMS Classi cation numbers Primary: 53C20 Secondary: 53C20, 58B20, 58G30

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تاریخ انتشار 1999