Paper · Jan 30, 2020

Curvature estimates and gap theorems for expanding Ricci solitons

Pak-Yeung Chan

As on arXiv

Abstract

We derive a sharp lower bound for the scalar curvature of non-flat and non-compact expanding gradient Ricci soliton provided that the scalar curvature is non-negative and the potential function is proper. We also give an upper bound for the scalar curvature of noncompact expander when the Ricci curvature is nonpositive and the potential function is proper. We then provide a sufficient condition for the scalar curvature of expanding soliton being nonnegative. We also estimate the curvature of expanding soliton in dimensions three and four. As an application, we prove a gap theorem on three dimensional gradient expander.

Submitted
Jan 30, 2020
Last revised
Aug 13, 2021 (v2)
Subjects
math.DG

Comments: 33 pages. Theorem 6 improved

Its neighbourhood

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 2016, 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 Curvature estimates for steady Ricci solitons (Pak-Yeung Chan, 2019)5Chan 2019 Hamilton-Ivey estimates for gradient Ricci solitons (Pak-Yeung Chan, Zilu Ma and Yongjia Zhang, 2021)4Chan 2021 Rigidity results for shrinking and expanding Ricci solitons (Benedito Leandro and Jeferson Poveda, 2022)3Leandro 2022 A local gap theorem for Ricci shrinkers (Pak-Yeung Chan, Zilu Ma and Yongjia Zhang, 2022)8Chan 2022 Gap Theorem on Riemannian manifolds using Ricci flow (Pak-Yeung Chan and Man-Chun Lee, 2023)2Chan 2023 On noncollapsed F-limit metric solitons (Pak-Yeung Chan, Zilu Ma and Yongjia Zhang, 2024)7Chan 2024 Curvature estimates for steady and expanding solitons in higher dimensions (Pak-Yeung Chan and Ming Hsiao, 2025)1Chan 2025 Rigidity and gap theorems for Ricci shrinkers (Pak-Yeung Chan and Yongjia Zhang, 2026)6Chan 2026
Closer to the centre: more closely connected. Clockwise from the top: oldest to newest. Ricci flowWider flowsalso connected to each other
  1. Curvature estimates for steady and expanding solitons in higher dimensions

    Pak-Yeung Chan and Ming Hsiao

    Topics Boundaries & non-compact, Ricci solitons · Same author Pak-Yeung Chan · Shared terms “expanding solitons”, “curvature estimates”, “potential function”

  2. Gap Theorem on Riemannian manifolds using Ricci flow

    Pak-Yeung Chan and Man-Chun Lee

    Topics 3-manifolds, Boundaries & non-compact · Same author Pak-Yeung Chan · Shared terms “gap theorem”, “curvature estimates”

  3. Rigidity results for shrinking and expanding Ricci solitons

    Benedito Leandro and Jeferson Poveda

    Topics Scalar curvature, Boundaries & non-compact, Ricci solitons · Shared terms “expanding Ricci”, “potential function”

  4. Hamilton-Ivey estimates for gradient Ricci solitons

    Pak-Yeung Chan, Zilu Ma and Yongjia Zhang

    Topics 3-manifolds, Ricci solitons · Same author Pak-Yeung Chan · Shared terms “potential function”, “expanders”, “dimensional gradient”

  5. Curvature estimates for steady Ricci solitons

    Pak-Yeung Chan

    Topics Scalar curvature, Ricci solitons · Same author Pak-Yeung Chan · Shared terms “curvature estimates”, “potential function”

  6. Rigidity and gap theorems for Ricci shrinkers

    Pak-Yeung Chan and Yongjia Zhang

    Topics Ricci solitons · Same author Pak-Yeung Chan · Shared terms “gap theorem”

  7. On noncollapsed -limit metric solitons

    Pak-Yeung Chan, Zilu Ma and Yongjia Zhang

    Topics Scalar curvature, Ricci solitons · Same author Pak-Yeung Chan · Shared terms “gap theorem”, “lower bound”

  8. A local gap theorem for Ricci shrinkers

    Pak-Yeung Chan, Zilu Ma and Yongjia Zhang

    Topics Ricci solitons · Same author Pak-Yeung Chan · Shared terms “gap theorem”, “potential function”

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