$L^2$ curvature pinching theorems and vanishing theorems on complete Riemannian manifolds

Yuxin Dong; Hezi Lin; Shihshu Walter Wei

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arXiv · 1604.04862

$L^2$ curvature pinching theorems and vanishing theorems on complete Riemannian manifolds

Yuxin Dong·Hezi Lin·Shihshu Walter Wei

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Abstract

In this paper, by using monotonicity formulas for vector bundle-valued $p$-forms satisfying the conservation law, we first obtain general $L^2$ global rigidity theorems for locally conformally flat (LCF) manifolds with constant scalar curvature, under curvature pinching conditions. Secondly, we prove vanishing results for $L^2$ and some non-$L^2$ harmonic $p$-forms on LCF manifolds, by assuming that the underlying manifolds satisfy pointwise or integral curvature conditions. Moreover, by a Theorem of Li-Tam for harmonic functions, we show that the underlying manifold must have only one end. Finally, we obtain Liouville theorems for $p$-harmonic functions on LCF manifolds under pointwise Ricci curvature conditions.

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BibTeX RIS

Yuxin Dong, Hezi Lin, Shihshu Walter Wei. 2016-04-17. $L^2$ curvature pinching theorems and vanishing theorems on complete Riemannian manifolds. https://arxiv.org/abs/1604.04862

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