Lichnerowicz-Obata Estimate, Almost Parallel $p$-form and Almost Product Manifolds

Masayuki Aino

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arXiv · 1904.06533

Lichnerowicz-Obata Estimate, Almost Parallel $p$-form and Almost Product Manifolds

Masayuki Aino

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Abstract

We show a Lichnerowicz-Obata type estimate for the first eigenvalue of the Laplacian of $n$-dimensional closed Riemannian manifolds with an almost parallel $p$-form ($2\leq p \leq n/2$) in $L^2$-sense, and give an almost decomposition result of the manifold under some pinching conditions when $2\leq p<n/2$.

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BibTeX RIS

Masayuki Aino. 2019-04-13. Lichnerowicz-Obata Estimate, Almost Parallel $p$-form and Almost Product Manifolds. https://arxiv.org/abs/1904.06533

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