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Myers-type compactness theorem with the Bakry-Emery Ricci tensor

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 نشر من قبل Sanghun Lee
 تاريخ النشر 2019
  مجال البحث
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In this paper, we first prove the $f$-mean curvature comparison in a smooth metric measure space when the Bakry-Emery Ricci tensor is bounded from below and $|f|$ is bounded. Based on this, we define a Myers-type compactness theorem by generalizing the results of Cheeger, Gromov, and Taylor and of Wan for the Bakry-Emery Ricci tensor. Moreover, we improve a result from Soylu by using a weaker condition on a derivative $f(t)$.

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