Paper · Jul 5, 2024

Sharpening a gap theorem: nonnegative Ricci and small curvature concentration

Adam Martens

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Abstract

We sharpen a gap theorem of Chan & Lee for nonnegative Ricci curvature manifolds that have positive asymptotic volume ratio and small enough scale-invariant integral curvature (so-called "curvature concentration"), by showing that the curvature concentration need only depend linearly on the asymptotic volume ratio. We prove the result by exhibiting a long-time Ricci flow solution with faster than curvature decay, which allows us to shift the limiting contradiction argument to time infinity and thus obtain an explicit bound on the size of the gap.

Comments: To appear in Calculus of Variations and Partial Differential Equations. Final version

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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 Manifolds with small curvature concentration (Pak-Yeung Chan, Shaochuang Huang and Man-Chun Lee, 2022)2Chan 2022 Pseudolocality and completeness for nonnegative Ricci curvature limits of 3D singular Ricci flows (Albert Chau and Adam Martens, 2023)6Chau 2023 Long-time Ricci flow existence and topological rigidity from manifolds with pinched scale-invariant integral curvature (Albert Chau and Adam Martens, 2024)4Chau 2024 Removing scalar curvature assumption for Ricci flow smoothing (Adam Martens, 2024)3Martens 2024 A note on a diffeomorphism criterion via long-time Ricci flow (Shaochuang Huang and Zhuo Peng, 2025)5Huang 2025 A note on Ricci flow from small curvature concentration and a Morrey-type condition (Albert Chau and Adam Martens, 2026)1Chau 2026 Rigidity and gap theorems for Ricci shrinkers (Pak-Yeung Chan and Yongjia Zhang, 2026)8Chan 2026 A gap theorem for metric solitons and its applications (Ganqi Wang and Yongjia Zhang, 2026)7Wang 2026
Closer to the centre: more closely connected. Clockwise from the top: oldest to newest. Ricci flowWider flowsalso connected to each other
  1. A note on Ricci flow from small curvature concentration and a Morrey-type condition

    Albert Chau and Adam Martens PDF

    Topics Ricci flow · Same author Adam Martens · Shared terms “curvature concentration”, “small curvature”, “invariant integral”

  2. Manifolds with small curvature concentration

    Pak-Yeung Chan, Shaochuang Huang and Man-Chun Lee PDF

    Topics Ricci flow · Shared terms “curvature concentration”, “small curvature”

  3. Removing scalar curvature assumption for Ricci flow smoothing

    Adam Martens PDF

    Topics Ricci flow · Same author Adam Martens · Shared terms “curvature concentration”, “volume ratio”, “small enough”

  4. Long-time Ricci flow existence and topological rigidity from manifolds with pinched scale-invariant integral curvature

    Albert Chau and Adam Martens PDF

    Topics Ricci flow · Same author Adam Martens · Shared terms “invariant integral”, “time Ricci”, “integral curvature”

  5. A note on a diffeomorphism criterion via long-time Ricci flow

    Shaochuang Huang and Zhuo Peng PDF

    Topics Ricci flow · Shared terms “curvature concentration”, “small curvature”, “time Ricci”

  6. Pseudolocality and completeness for nonnegative Ricci curvature limits of 3D singular Ricci flows

    Albert Chau and Adam Martens PDF

    Topics Ricci flow · Same author Adam Martens · Shared terms “nonnegative Ricci”, “volume ratio”

  7. A gap theorem for metric solitons and its applications

    Ganqi Wang and Yongjia Zhang PDF

    Topics Ricci flow · Shared terms “gap theorem”, “volume ratio”, “asymptotic volume”

  8. Rigidity and gap theorems for Ricci shrinkers

    Pak-Yeung Chan and Yongjia Zhang PDF

    Topics Ricci flow · Shared terms “gap theorem”

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Background reading

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In the guidebook

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    Uniformization and the Two-Dimensional Ricci FlowBook 5A · Complex Analysis and Conformal Geometry

    Constant-curvature metrics on surfaces, and Ricci flow as a heat equation for the conformal factor.

  2. 10A.12
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  3. 11A.1
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    A heat equation for the metric: spheres, cylinders and scaling.