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arXiv · 2103.13379

The singular set in the Stefan problem

Alessio Figalli·Xavier Ros-Oton·Joaquim Serra
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Abstract

In this paper we analyze the singular set in the Stefan problem and prove the following results: - The singular set has parabolic Hausdorff dimension at most $n-1$. - The solution admits a $C^\infty$-expansion at all singular points, up to a set of parabolic Hausdorff dimension at most $n-2$. - In $\mathbb R^3$, the free boundary is smooth for almost every time $t$, and the set of singular times $\mathcal S\subset \mathbb R$ has Hausdorff dimension at most $1/2$. These results provide us with a refined understanding of the Stefan problem's singularities and answer some long-standing open questions in the field.

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Alessio Figalli, Xavier Ros-Oton, Joaquim Serra. 2021-03-24. The singular set in the Stefan problem. https://arxiv.org/abs/2103.13379

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