Paper · Aug 14, 2025

Geometric Structure of Ends of Ricci Shrinkers

Alessandro Bertellotti, Reto Buzano

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Abstract

We study blow-up sequences of Ricci shrinkers without global curvature assumptions based at points at which the scalar curvature satisfies a Type I bound, proving that their -limits split a line. In the four-dimensional case these limits are smooth Ricci shrinkers and the convergence is in the pointed smooth Cheeger-Gromov sense. As a consequence, limits along the integral curve of starting at such a point split a line. This generalises known results about the geometry of ends of Ricci shrinkers that relied on global curvature bounds. To obtain our results, we extend the -convergence theory from Bamler and Li-Wang.

Comments: 47 pages. All comments welcome

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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.

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  1. Ends of (singular) Ricci shrinkers

    Alessandro Bertellotti and Reto Buzano PDF

    Topics Ricci solitons · Same authors Alessandro Bertellotti, Reto Buzano · Shared terms “Ricci shrinkers”, “sequence”

  2. A Local Singularity Analysis for the Ricci Flow and its Applications to Ricci Flows with Bounded Scalar Curvature – Part II

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    Topics Scalar curvature, Singularities · Same author Reto Buzano · Shared terms “curvature bounds”

  3. Curvature Bounds on Ricci flows with bounded scalar curvature up to dimension 7

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    Topics 4-manifolds, Scalar curvature · Shared terms “curvature bounds”, “Bamler”

  4. Curvature estimates for four-dimensional complete gradient expanding Ricci solitons

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    Topics 4-manifolds, Scalar curvature, Ricci solitons · Shared terms “four dimensional”

  5. Gromov-Hausdorff Limits of Noncollapsed Kähler-Ricci Flows and the Geometry of Ricci Shrinkers

    Yu Li and Junsheng Zhang PDF

    Topics 4-manifolds, Scalar curvature, Singularities · Shared terms “Ricci shrinkers”, “Gromov”, “four dimensional”

  6. A note on four dimensional Shrinking Gradient Ricci Solitons with Constant Scalar Curvature

    Chen Wang and Guoqiang Wu PDF

    Topics 4-manifolds, Scalar curvature, Ricci solitons · Shared terms “four dimensional”

  7. A note on Rigidity of Shrinking Gradient Ricci Solitons with Constant Scalar Curvature

    Chen Wang and Guoqiang Wu PDF

    Topics 4-manifolds, Scalar curvature, Ricci solitons · Shared terms “Ricci shrinkers”, “four dimensional”

  8. On curvature estimates for four-dimensional gradient Ricci solitons

    Huai-Dong Cao PDF

    Topics 4-manifolds, Ricci solitons · Shared terms “Ricci shrinkers”, “four dimensional”

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