A General Schwarz Lemma for Almost-hermitian Manifolds
نویسنده
چکیده
We prove a version of Yau’s Schwarz Lemma for general almost-complex manifolds equipped with almost-Hermitian metrics. This requires an extension to this setting of the Laplacian comparison theorem. As an application we show that the product of two almost-complex manifolds does not admit any complete almost-Hermitian metric with bisectional curvature bounded between two negative constants that satisfies some additional assumptions.
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