# The Weyl functional on 4-manifolds of positive Yamabe invariant

@article{Sung2021TheWF,
title={The Weyl functional on 4-manifolds of positive Yamabe invariant},
author={Chanyoung Sung},
journal={Annals of Global Analysis and Geometry},
year={2021}
}
• Chanyoung Sung
• Published 9 August 2021
• Mathematics
• Annals of Global Analysis and Geometry
W + g , χ ( M ) and τ ( M ) respectively, the self-dual Weyl tensor of g , the Euler characteristic and the signature of M . This generalizes M. J. Gursky inequality Math. (2) for the case of b 1 ( M ) > 0 in a much simpler way. He also extends all such lower bounds of the Weyl functional to 4-orbifolds including Gursky’s inequalities for the case of b +2 ( M ) > 0 or δ g W + g = 0 and obtain topological obstructions to the existence of self-dual orbifold metrics of positive scalar curvature.
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