1/4-Pinched Contact Sphere Theorem

Jian Ge; Yang Huang

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arXiv · 1304.5224

1/4-Pinched Contact Sphere Theorem

Jian Ge·Yang Huang

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Abstract

Given a closed contact 3-manifold with a compatible Riemannian metric, we show that if the sectional curvature is 1/4-pinched, then the contact structure is universally tight. This result improves the Contact Sphere Theorem in [EKM12], where a 4/9-pinching constant was imposed. Some tightness results on positively curved contact open 3-manifold are also discussed.

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Jian Ge, Yang Huang. 2013-04-18. 1/4-Pinched Contact Sphere Theorem. https://arxiv.org/abs/1304.5224

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