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arXiv · 1304.0721

Extensions and fill-ins with nonnegative scalar curvature

Jeffrey Jauregui·Pengzi Miao·Luen-Fai Tam
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Abstract

Motivated by the quasi-local mass problem in general relativity, we apply the asymptotically flat extensions, constructed by Shi and Tam in the proof of the positivity of the Brown--York mass, to study a fill-in problem of realizing geometric data on a 2-sphere as the boundary of a compact 3-manifold of nonnegative scalar curvature. We characterize the relationship between two borderline cases: one in which the Shi--Tam extension has zero total mass, and another in which fill-ins of nonnegative scalar curvature fail to exist. Additionally, we prove a type of positive mass theorem in the latter case.

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Jeffrey Jauregui, Pengzi Miao, Luen-Fai Tam. 2013-04-02. Extensions and fill-ins with nonnegative scalar curvature. https://doi.org/10.1088/0264-9381%2F30%2F19%2F195007

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