Harmonic two-forms in four dimensions

Seaman, Walter

doi:10.1090/S0002-9939-1991-1062836-0

Harmonic two-forms in four dimensions
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Proc. Amer. Math. Soc. 112 (1991), 545-548 Request permission

Abstract:

Conformal invariance of middle-dimensional harmonic forms is used to improve Kato’s inequality for four-manifolds. An application to positively curved four-manifolds is given.

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