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Closed almost-Kahler 4-manifolds of constant non-negative Hermitian holomorphic sectional curvature are Kahler

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 نشر من قبل Mehdi Lejmi
 تاريخ النشر 2017
  مجال البحث
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We show that a closed almost Kahler 4-manifold of globally constant holomorphic sectional curvature $kgeq 0$ with respect to the canonical Hermitian connection is automatically Kahler. The same result holds for $k<0$ if we require in addition that the Ricci curvature is J-invariant. The proofs are based on the observation that such manifolds are self-dual, so that Chern-Weil theory implies useful integral formulas, which are then combined with results from Seiberg--Witten theory.



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