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Ricci flow and contractibility of spaces of metrics

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 نشر من قبل Richard H. Bamler
 تاريخ النشر 2019
  مجال البحث
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We show that the space of metrics of positive scalar curvature on any 3-manifold is either empty or contractible. Second, we show that the diffeomorphism group of every 3-dimensional spherical space form deformation retracts to its isometry group. This proves the Generalized Smale Conjecture. Our argument is independent of Hatchers theorem in the $S^3$ case and in particular it gives a new proof of the $S^3$ case.

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