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1. Mean curvature flow from conical singularities

   https://doi.org/10.1007/s00222-024-01296-8  

   Chodosh, Otis; Daniels-Holgate, J M; Schulze, Felix (December 2024, Inventiones mathematicae)

   Abstract We prove Ilmanen’s resolution of point singularities conjecture by establishing short-time smoothness of the level set flow of a smooth hypersurface with isolated conical singularities. This shows how the mean curvature flow evolves through asymptotically conical singularities. Precisely, we prove that the level set flow of a smooth hypersurface$$M^{n}\subset \mathbb{R}^{n+1}$$ $M^n\subset R^{n+1}$,$$2\leq n\leq 6$$ $2\le n\le 6$, with an isolated conical singularity is modeled on the level set flow of the cone. In particular, the flow fattens (instantaneously) if and only if the level set flow of the cone fattens. 

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2. Local Well-Posedness of Skew Mean Curvature Flow for Small Data in $$d\ge 4$$ Dimensions

   https://doi.org/10.1007/s00220-021-04303-8  

   Huang, Jiaxi; Tataru, Daniel (January 2022, Communications in Mathematical Physics)

   Abstract The skew mean curvature flow is an evolution equation forddimensional manifolds embedded in$${{\mathbb {R}}}^{d+2}$$ $R^{d+2}$(or more generally, in a Riemannian manifold). It can be viewed as a Schrödinger analogue of the mean curvature flow, or alternatively as a quasilinear version of the Schrödinger Map equation. In this article, we prove small data local well-posedness in low-regularity Sobolev spaces for the skew mean curvature flow in dimension$$d\ge 4$$ $d\ge 4$. 

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3. Local Well-Posedness of the Skew Mean Curvature Flow for Small Data in $$d\geqq 2$$ Dimensions

   https://doi.org/10.1007/s00205-023-01952-y  

   Huang, Jiaxi; Tataru, Daniel (January 2024, Archive for Rational Mechanics and Analysis)

   Abstract The skew mean curvature flow is an evolution equation forddimensional manifolds embedded in$${\mathbb {R}}^{d+2}$$ $R^{d+2}$(or more generally, in a Riemannian manifold). It can be viewed as a Schrödinger analogue of the mean curvature flow, or alternatively as a quasilinear version of the Schrödinger Map equation. In an earlier paper, the authors introduced a harmonic/Coulomb gauge formulation of the problem, and used it to prove small data local well-posedness in dimensions$$d \geqq 4$$ $d\geqq 4$. In this article, we prove small data local well-posedness in low-regularity Sobolev spaces for the skew mean curvature flow in dimension$$d\geqq 2$$ $d\geqq 2$. This is achieved by introducing a new, heat gauge formulation of the equations, which turns out to be more robust in low dimensions. 

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4. Ricci flow does not preserve positive sectional curvature in dimension four

   https://doi.org/10.1007/s00526-022-02335-z  

   Bettiol, Renato G.; Krishnan, Anusha M. (November 2022, Calculus of Variations and Partial Differential Equations)

   Abstract We find examples of cohomogeneity one metrics on$$S^4$$ $S^4$and$$\mathbb {C}P^2$$ $C{P}^2$with positive sectional curvature that lose this property when evolved via Ricci flow. These metrics are arbitrarily small perturbations of Grove–Ziller metrics with flat planes that become instantly negatively curved under Ricci flow. 

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5. Random 3-manifolds have no totally geodesic submanifolds

   https://doi.org/10.1007/s10455-025-09998-9  

   El-Hasan, Hasan M; Wilhelm, Frederick (May 2025, Annals of Global Analysis and Geometry)

   Agricola, Ilka; Bögelein, Verena (Ed.)

   Abstract Murphy and the second author showed that a generic closed Riemannian manifold has no totally geodesic submanifolds, provided the ambient space is at least four dimensional. Lytchak and Petrunin established a similar result in dimension 3. For the higher dimensional result, the “generic set” is open and dense in the$$C^{q}$$ $C^q$–topology for any$$q\ge 2.$$ $q\ge 2.$In Lytchak and Petrunin’s work, the “generic set” is a dense$$G_{\delta }$$ $G_{\delta }$in the$$C^{q}$$ $C^q$–topology for any$$q\ge 2.$$ $q\ge 2.$Here we show that the set of such metrics on a compact 3–manifold actually contains a set that is that is open and dense set in the$$C^{q}$$ $C^q$–topology, provided$$q\ge 3.$$ $q\ge 3.$ 

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