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Almost-rigidity and the extinction time of positively curved Ricci flows

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 Added by Davi Maximo
 Publication date 2015
  fields
and research's language is English




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We prove that Ricci flows with almost maximal extinction time must be nearly round, provided that they have positive isotropic curvature when crossed with $mathbb{R}^{2}$. As an application, we show that positively curved metrics on $S^{3}$ and $RP^{3}$ with almost maximal width must be nearly round.



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