The Weyl functional on 4-manifolds of positive Yamabe invariant

  title={The Weyl functional on 4-manifolds of positive Yamabe invariant},
  author={Chanyoung Sung},
  journal={Annals of Global Analysis and Geometry},
  • 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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