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NOTES ON A QUESTION RAISED BY E. CALABI
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 Title & Authors
NOTES ON A QUESTION RAISED BY E. CALABI
Euh, Yunhee; Sekigawa, Kouei;
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 Abstract
We show that any orthogonal almost complex structure on a warped product Riemannian manifold of an oriented closed surface with nonnegative Gaussian curvature and a round 4-sphere is never integrable. This provides a partial answer to a question raised by E. Calabi.
 Keywords
orthogonal complex structure;warped product;curvature identity;
 Language
English
 Cited by
 References
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