Paper · Sep 28, 2026

Counterexamples to preservation of flat normal bundles under mean curvature flow

Keita Kunikawa

math.DGWider flowsarXiv:2609.34291v2
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Abstract

We construct an embedded torus and an entire graph in whose normal bundles are initially flat but lose this property instantaneously under mean curvature flow. We also give an example showing that the parallel principal normal condition is not preserved under mean curvature flow, even though the normal bundle remains flat along the flow.

Comments: 23 pages. Revised Section 5 and made minor improvements throughout the manuscript

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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 Uniqueness of entire graphs evolving by Mean Curvature flow (Panagiota Daskalopoulos and Mariel Saez, 2021)1Daskalopoulo 2021 Gaussian heat kernel estimates of Bamler-Zhang type along super Ricci flow (Keita Kunikawa and Yohei Sakurai, 2022)3Kunikawa 2022 Generic mean curvature flows with cylindrical singularities I: the normal forms and nondegeneracy (Ao Sun and Jinxin Xue, 2022)5Sun 2022 Almost splitting and quantitative stratification for super Ricci flow (Keita Kunikawa and Yohei Sakurai, 2023)4Kunikawa 2023 Singularity formation along the line bundle mean curvature flow (Yu Hin Chan and Adam Jacob, 2023)7Chan 2023 Codimension two mean curvature flow of entire graphs (Andreas Savas-Halilaj and Knut Smoczyk, 2024)2Savas-Halila 2024 Expanders for Mean Curvature Flow and Counterexamples to Ilmanen's Genus-Reduction Conjecture (David Hoffman, Francisco Martin and Brian White, 2026)6Hoffman 2026 Genus Increase in Closed Mean Curvature Flows (Jingwen Chen, 2026)8Chen 2026
Closer to the centre: more closely connected. Clockwise from the top: oldest to newest. Ricci flowWider flowsalso connected to each other
  1. Uniqueness of entire graphs evolving by Mean Curvature flow

    Panagiota Daskalopoulos and Mariel SaezWider flows PDF

    Topics Mean curvature flow · Shared terms “entire graph”

  2. Codimension two mean curvature flow of entire graphs

    Andreas Savas-Halilaj and Knut SmoczykWider flows PDF

    Topics Mean curvature flow · Shared terms “entire graph”, “preserved”

  3. Genus Increase in Closed Mean Curvature Flows

    Jingwen Chen PDF

    Topics Mean curvature flow · Shared terms “counterexamples”

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