Abstract
We prove that if a compact Riemannian 4-manifold with positive sectional curvature satisfies a strengthened Kato type inequality, then it is definite. We also discuss some new insights for compact Riemannian 4-manifolds with positive sectional curvature.
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In Memory of Professor Zhengguo Bai (1916–2015)
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Liu, K., Wan, J. Harmonic 2-forms and positively curved 4-manifolds. Sci. China Math. 64, 1613–1620 (2021). https://doi.org/10.1007/s11425-019-1641-9
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DOI: https://doi.org/10.1007/s11425-019-1641-9