• Corpus ID: 245502941

Ricci flow does not preserve positive sectional curvature in dimension four

  title={Ricci flow does not preserve positive sectional curvature in dimension four},
  author={Renato G. Bettiol and Anusha M. Krishnan},
We find examples of cohomogeneity one metrics on S and CP 2 with positive sectional curvature that lose this property when evolved via Ricci flow. These metrics are arbitrarily small perturbations of Grove–Ziller metrics with flat planes that become instantly negatively curved under Ricci flow. 
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