Paper · May 16, 2025

An Intersection Principle for Mean Curvature Flow

Tang-Kai Lee, Alec Payne

math.DGWider flowsarXiv:2505.11600
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Abstract

The avoidance principle says that mean curvature flows of hypersurfaces remain disjoint if they are disjoint at the initial time. We prove several generalizations of the avoidance principle that allow for intersections of hypersurfaces. First, we prove that the Hausdorff dimension of the intersection of two mean curvature flows is non-increasing over time, and we find precise information on how the dimension changes. We then show that the self-intersection of an immersed mean curvature flow has non-increasing dimension over time. Next, we extend the intersection dimension monotonicity to Brakke flows and level set flows which satisfy a localizability condition, and we provide examples showing that the monotonicity fails for general weak solutions. We find a localization result for level set flows with finitely many singularities, and as a consequence, we obtain a fattening criterion for these flows which depends on the behavior of intersections with smooth flows.

Comments: 39 pages, 4 figures. Comments welcome!

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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 Generic regularity of Level Set Flows with spherical singularity (Ao Sun and Jinxin Xue, 2022)4Sun 2022 Generic level sets in mean curvature flow are BV solutions (Anton Ullrich and Tim Laux, 2023)7Ullrich 2023 Mean Curvature Flow from Conical Singularities (Otis Chodosh, J. M. Daniels-Holgate and Felix Schulze, 2023)2Chodosh 2023 On the Multiplicity One Conjecture for Mean Curvature Flows of surfaces (Richard H Bamler and Bruce Kleiner, 2023)5Bamler 2023 Closed mean curvature flows with asymptotically conical singularities (Tang-Kai Lee and Xinrui Zhao, 2024)3Lee 2024 On the avoidance principle for codimension 1 space-time Brakke flows (Abdelmouksit Sagueni, 2025)1Sagueni 2025 Equivalence of weak solution concepts for mean curvature flow (Tim Laux and Anton Ullrich, 2025)8Laux 2025 Quantitative avoidance for free boundary flows and applications (Yueheng Bao and Robert Haslhofer, 2026)6Bao 2026
Closer to the centre: more closely connected. Clockwise from the top: oldest to newest. Ricci flowWider flowsalso connected to each other
  1. On the avoidance principle for codimension 1 space-time Brakke flows

    Abdelmouksit SagueniWider flows PDF

    Topics Weak & singular flows · Shared terms “avoidance principle”, “Brakke flows”

  2. Mean Curvature Flow from Conical Singularities

    Otis Chodosh, J. M. Daniels-Holgate and Felix SchulzeWider flows PDF

    Topics Weak & singular flows, Singularities · Shared terms “set flow”, “level set”

  3. Closed mean curvature flows with asymptotically conical singularities

    Tang-Kai Lee and Xinrui Zhao PDF

    Topics Weak & singular flows, Singularities · Same author Tang-Kai Lee · Shared terms “set flow”, “level set”, “fattening”

  4. Generic regularity of Level Set Flows with spherical singularity

    Ao Sun and Jinxin Xue PDF

    Topics Weak & singular flows, Singularities · Shared terms “set flow”, “level set”

  5. On the Multiplicity One Conjecture for Mean Curvature Flows of surfaces

    Richard H Bamler and Bruce KleinerWider flows PDF

    Topics Weak & singular flows, Singularities · Shared terms “set flow”, “level set”, “fattening”

  6. Quantitative avoidance for free boundary flows and applications

    Yueheng Bao and Robert HaslhoferWider flows PDF

    Topics Weak & singular flows, Singularities · Shared terms “avoidance”, “Brakke flows”

  7. Generic level sets in mean curvature flow are BV solutions

    Anton Ullrich and Tim LauxWider flows PDF

    Topics Weak & singular flows · Shared terms “level set”, “Brakke flows”

  8. Equivalence of weak solution concepts for mean curvature flow

    Tim Laux and Anton UllrichWider flows PDF

    Topics Weak & singular flows · Shared terms “level set”, “Brakke flows”

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  3. 6C.8
    Monotonicity, ε-Regularity and Tangent ConesBook 6C · Nonlinear PDE: Variational and Geometric Methods

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