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arXiv · 1403.8000

One-dimensional projective structures, convex curves and the ovals of Benguria & Loss

Jacob Bernstein·Thomas Mettler
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Abstract

Benguria and Loss have conjectured that, amongst all smooth closed curves of length $2π$ in the plane, the lowest possible eigenvalue of the operator $L=-Δ+κ^2$ was one. They observed that this value was achieved on a two-parameter family, $\mathcal{O}$, of geometrically distinct ovals containing the round circle and collapsing to a multiplicity-two line segment. We characterize the curves in $\mathcal{O}$ as absolute minima of two related geometric functionals. We also discuss a connection with projective differential geometry and use it to explain the natural symmetries of all three problems.

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Jacob Bernstein, Thomas Mettler. 2014-08-27. One-dimensional projective structures, convex curves and the ovals of Benguria & Loss. https://doi.org/10.1007/s00220-014-2275-7

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