Paper · Feb 20, 2022

Singularities and diffeomorphisms

Tobias Holck Colding, William P. Minicozzi

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Abstract

Comparing and recognizing metrics can be extraordinarily difficult because of the group of diffeomorphisms. Two metrics, that could even be the same, could look completely different in different coordinates. This is the gauge problem. The general gauge problem is extremely subtle, especially for non-compact spaces. Often it can be avoided if one uses some additional structure of the particular situation. However, in many problems there is no additional structure. Instead we solve the gauge problem directly in great generality. The techniques and ideas apply to many problems. We use them to solve a well-known open problem in Ricci flow. We solve the gauge problem by solving a nonlinear system of PDEs. The PDE produces a diffeomorphism that fixes an appropriate gauge in the spirit of the slice theorem for group actions. We then show optimal bounds for the displacement function of the diffeomorphism.

Comments: arXiv admin note: substantial text overlap with arXiv:2109.06240

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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 Optimal growth bounds for eigenfunctions (Tobias Holck Colding and William P. Minicozzi, 2021)2Colding 2021 Singularities of Ricci flow and diffeomorphisms (Tobias Holck Colding and William P. Minicozzi, 2021)1Colding 2021 Closed Ricci Flows with Singularities Modeled on Asymptotically Conical Shrinkers (Maxwell Stolarski, 2022)8Stolarski 2022 Eigenvalue lower bounds and splitting for modified Ricci flow (Tobias Holck Colding and William P. Minicozzi, 2023)3Colding 2023 Propagation of symmetries for Ricci shrinkers (Tobias Holck Colding and William P. Minicozzi, 2023)6Colding 2023 A strong Frankel Theorem for shrinkers (Tobias Holck Colding and William P. Minicozzi, 2023)5Colding 2023 Quantitative uniqueness for mean curvature flow (Tobias Holck Colding and William P. Minicozzi, 2025)4Colding 2025 Distance between minimal surfaces and flows (Tobias Holck Colding and William P. Minicozzi, 2026)7Colding 2026
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  1. Singularities of Ricci flow and diffeomorphisms

    Tobias Holck Colding and William P. Minicozzi PDF

    Topics Boundaries & non-compact, Singularities · Same authors Tobias Holck Colding, William P. Minicozzi · Shared terms “additional structure”, “diffeomorphism”, “great generality”

  2. Optimal growth bounds for eigenfunctions

    Tobias Holck Colding and William P. Minicozzi PDF

    Topics Boundaries & non-compact · Same authors Tobias Holck Colding, William P. Minicozzi · Shared terms “compact spaces”, “diffeomorphism”, “extremely”

  3. Eigenvalue lower bounds and splitting for modified Ricci flow

    Tobias Holck Colding and William P. Minicozzi PDF

    Topics Ricci flow · Same authors Tobias Holck Colding, William P. Minicozzi

  4. Quantitative uniqueness for mean curvature flow

    Tobias Holck Colding and William P. MinicozziWider flows PDF

    Topics Singularities · Same authors Tobias Holck Colding, William P. Minicozzi

  5. A strong Frankel Theorem for shrinkers

    Tobias Holck Colding and William P. Minicozzi PDF

    Same authors Tobias Holck Colding, William P. Minicozzi

  6. Propagation of symmetries for Ricci shrinkers

    Tobias Holck Colding and William P. Minicozzi PDF

    Same authors Tobias Holck Colding, William P. Minicozzi

  7. Distance between minimal surfaces and flows

    Tobias Holck Colding and William P. MinicozziWider flows PDF

    Same authors Tobias Holck Colding, William P. Minicozzi · Shared terms “PDE”

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