Paper · Sep 25, 2026

Optimal regularity for the arrival time equation

Yiqi Huang, Jingze Zhu

math.DGWider flowsarXiv:2609.31610
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Abstract

For a convex mean curvature flow in , the corresponding arrival time function solves a degenerate elliptic equation that becomes singular at extinction. We prove that it is for any in the plane, with a logarithmic modulus for its twenty-fourth derivatives. We prove that this bound is sharp combining regularity obstruction in our companion paper. We obtain asymptotic expansions of the rescaled flow to any prescribed order, including derivative estimates for the remainder. Combined with the work of Sesum for , this also gives the sharp regularity for convex arrival time functions in higher dimensions.

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Connected papers

The 8 papers on this site closest to this one, judged by the topics they share, the words and phrases in their titles and abstracts, and their authors. They are not its citations, but a map of the work around it. Papers here go back to 2021, plus the canon.

Connected papers This paper in the centre and the 8 papers closest to it around it, in date order clockwise from the top. The closer a paper sits to the centre, the stronger the connection. This paper Quantitative long range curvature estimate for mean curvature flow (Jingze Zhu, 2021)5Zhu 2021 Spectral quantization for ancient asymptotically cylindrical flows (Wenkui Du and Jingze Zhu, 2022)8Du 2022 Arnold-Thom conjecture for the arrival time of surfaces (Tang-Kai Lee and Jingze Zhu, 2024)2Lee 2024 Rigidity of ancient ovals in higher dimensional mean curvature flow (Beomjun Choi, Wenkui Du and Jingze Zhu, 2025)6Choi 2025 Planarity and convexity for pinched ancient solutions of mean curvature flow (Tang-Kai Lee, Keaton Naff and Jingze Zhu, 2025)7Lee 2025 The Bounded Diameter Conjecture and Sharp Geometric Estimates for Mean Curvature Flow (Yiqi Huang and Wenshuai Jiang, 2025)3Huang 2025 On the rate of convergence of cylindrical singularity in mean curvature flow (Yiqi Huang and Xinrui Zhao, 2025)4Huang 2025 General regularity obstructions for the arrival time equation (Yiqi Huang and Jingze Zhu, 2026)1Huang 2026
Closer to the centre: more closely connected. Clockwise from the top: oldest to newest. Ricci flowWider flowsalso connected to each other
  1. General regularity obstructions for the arrival time equation

    Yiqi Huang and Jingze ZhuWider flows PDF

    Topics Mean curvature flow · Same authors Yiqi Huang, Jingze Zhu · Shared terms “arrival time”, “time equation”, “time function”

  2. Arnold-Thom conjecture for the arrival time of surfaces

    Tang-Kai Lee and Jingze ZhuWider flows PDF

    Topics Mean curvature flow · Same author Jingze Zhu · Shared terms “arrival time”, “time function”, “convex mean”

  3. The Bounded Diameter Conjecture and Sharp Geometric Estimates for Mean Curvature Flow

    Yiqi Huang and Wenshuai JiangWider flows PDF

    Topics Mean curvature flow · Same author Yiqi Huang

  4. On the rate of convergence of cylindrical singularity in mean curvature flow

    Yiqi Huang and Xinrui ZhaoWider flows PDF

    Topics Mean curvature flow · Same author Yiqi Huang · Shared terms “rescaled”

  5. Quantitative long range curvature estimate for mean curvature flow

    Jingze ZhuWider flows PDF

    Topics Mean curvature flow · Same author Jingze Zhu · Shared terms “rescaled”

  6. Rigidity of ancient ovals in higher dimensional mean curvature flow

    Beomjun Choi, Wenkui Du and Jingze ZhuWider flows PDF

    Topics Mean curvature flow · Same author Jingze Zhu · Shared terms “Sesum”

  7. Spectral quantization for ancient asymptotically cylindrical flows

    Wenkui Du and Jingze ZhuWider flows PDF

    Topics Mean curvature flow · Same author Jingze Zhu

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