Scalar curvature and connected sums of self-dual 4-manifolds

Kalafat, Mustafa
Under a reasonable vanishing hypothesis, Donaldson and Friedman proved that the connected sum of two self-dual Riemannian 4-manifolds is again self-dual. Here we prove that the same result can be extended to the positive scalar curvature case. This is an analogue of the classical theorem of Gromov-Lawson and Schoen-Yau in the self-dual category. The proof is based on twistor theory.


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Citation Formats
M. Kalafat, “Scalar curvature and connected sums of self-dual 4-manifolds,” JOURNAL OF THE EUROPEAN MATHEMATICAL SOCIETY, pp. 883–898, 2011, Accessed: 00, 2020. [Online]. Available: