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arXiv · 2506.08387

On the singular set of the free boundary for a Monge-Amp\`ere obstacle problem

Tianling Jin·Xushan Tu·Jingang Xiong
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Abstract

This is a continuation of our earlier work [14] on the Monge-Amp\`ere obstacle problem \[ \det D^2 v = v^q \chi_{\{v>0\}}, \quad v \geq 0 \text{ convex} \] with $q \in [0,n)$, where we studied the regularity of the strictly convex part of the free boundary. In this work, we examine the non-strictly convex part of the free boundary and establish optimal dimension bounds for its flat portion. Additionally, we investigate the strong maximum principle and a stability property for this Monge-Amp\`ere obstacle problem.

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Tianling Jin, Xushan Tu, Jingang Xiong. 2025-06-10. On the singular set of the free boundary for a Monge-Amp\`ere obstacle problem. https://arxiv.org/abs/2506.08387

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