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arXiv · 1708.06567

Minimal two-spheres in three-spheres

Robert Haslhofer·Daniel Ketover
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Abstract

We prove that any manifold diffeomorphic to $S^3$ and endowed with a generic metric contains at least two embedded minimal two-spheres. The existence of at least one minimal two-sphere was obtained by Simon-Smith in 1983. Our approach combines ideas from min-max theory and mean curvature flow. We also establish the existence of smooth mean convex foliations in three manifolds. We apply our methods to solve a problem posed by S.T. Yau in 1987 on whether the planar two-spheres are the only minimal spheres in ellipsoids centered about the origin in $\mathbb{R}^4$. Finally, considering the example of degenerating ellipsoids we show that the assumptions in the multiplicity one conjecture and the equidistribution of widths conjecture are in a certain sense sharp.

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Robert Haslhofer, Daniel Ketover. 2017-08-22. Minimal two-spheres in three-spheres. https://doi.org/10.1215/00127094-2019-0009

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