Self-duality and differentiable structures on the connected sum of complex projective planes

Authors:
Henrik Pedersen and Yat Sun Poon

Journal:
Proc. Amer. Math. Soc. **121** (1994), 859-864

MSC:
Primary 32L25; Secondary 32J17, 53C56, 57R55

DOI:
https://doi.org/10.1090/S0002-9939-1994-1195729-1

MathSciNet review:
1195729

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Abstract | References | Similar Articles | Additional Information

Abstract: It is proved that if the twistor space of a self-dual four-manifold of positive scalar curvature contains a real effective divisor of degree two, then the four-manifold is diffeomorphic to the connected sum of *n* complex projective planes for some *n*. It follows that if the four-manifold is known to be homeomorphic to , then it is also diffeomorphic to .

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1994-1195729-1

Article copyright:
© Copyright 1994
American Mathematical Society