Paper · Aug 20, 2024

Semi-Continuity of the Morse Index for Ricci Shrinkers

Louis Yudowitz

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Abstract

We prove lower and upper semi-continuity of the Morse index for sequences of gradient Ricci shrinkers which bubble tree converge in the sense of past work by the author and Buzano. Our proofs rely on adapting recent arguments of Workman which were used to study certain sequences of CMC hypersurfaces and were in turn adapted from work on Da Lio-Gianocca-Riviere. Moreover, we are able to refine Workman's methods by using techniques related to polynomially weighted Sobolev spaces. This all also requires us to extend the analysis to handle when the shrinkers we study are non-compact, which we can do due to the availability of a suitable notion of finite weighted volume. Finally, we identify a technical condition which ensures the Morse index of an asymptotically conical shrinker is bounded below by the f-index of its asymptotic cone.

Comments: 44 pages. Final version, to appear in the Journal of Geometric Analysis

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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 Bubble-Tree Convergence and Local Diffeomorphism Finiteness for Gradient Ricci Shrinkers (Reto Buzano and Louis Yudowitz, 2022)1Buzano 2022 The spinorial energy for asymptotically Euclidean Ricci flow (Julius Baldauf and Tristan Ozuch, 2022)4Baldauf 2022 Ancient mean curvature flows from minimal hypersurfaces (Yongheng Han, 2023)3Han 2023 Dynamical Stability and Instability of Poincaré–Einstein Manifolds (Klaus Kroencke and Louis Yudowitz, 2023)8Kroencke 2023 Ancient mean curvature flows with finite total curvature (Kyeongsu Choi, Jiuzhou Huang and Taehun Lee, 2024)6Choi 2024 Ends of (singular) Ricci shrinkers (Alessandro Bertellotti and Reto Buzano, 2024)7Bertellotti 2024 Singularities of mean curvature flow with bounded mean curvature and Morse index (Yongheng Han, 2025)2Han 2025 On the geometry of asymptotically conical Ricci shrinkers (I): weighted analysis (Yu Li, Longhuan Yan and Wenjia Zhang, 2026)5Li 2026
Closer to the centre: more closely connected. Clockwise from the top: oldest to newest. Ricci flowWider flowsalso connected to each other
  1. Bubble-Tree Convergence and Local Diffeomorphism Finiteness for Gradient Ricci Shrinkers

    Reto Buzano and Louis Yudowitz PDF

    Topics Discrete & graph Ricci, Ricci solitons · Same author Louis Yudowitz · Shared terms “bubble tree”, “Ricci shrinkers”, “sequence”

  2. Ancient mean curvature flows from minimal hypersurfaces

    Yongheng HanWider flows PDF

    Topics Minimal & CMC surfaces · Shared terms “Morse index”

  3. The spinorial energy for asymptotically Euclidean Ricci flow

    Julius Baldauf and Tristan Ozuch PDF

    Topics Minimal & CMC surfaces, Boundaries & non-compact

  4. On the geometry of asymptotically conical Ricci shrinkers (I): weighted analysis

    Yu Li, Longhuan Yan and Wenjia Zhang PDF

    Topics Boundaries & non-compact, Ricci solitons · Shared terms “Ricci shrinkers”, “weighted Sobolev”, “asymptotically conical”

  5. Ancient mean curvature flows with finite total curvature

    Kyeongsu Choi, Jiuzhou Huang and Taehun LeeWider flows PDF

    Topics Minimal & CMC surfaces · Shared terms “Morse index”

  6. Ends of (singular) Ricci shrinkers

    Alessandro Bertellotti and Reto Buzano PDF

    Topics Boundaries & non-compact, Ricci solitons · Shared terms “Ricci shrinkers”, “sequence”, “asymptotically conical”

  7. Dynamical Stability and Instability of Poincaré–Einstein Manifolds

    Klaus Kroencke and Louis Yudowitz PDF

    Topics Boundaries & non-compact, Ricci solitons · Same author Louis Yudowitz

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