Total Mean Curvature and Closed Geodesics
نویسندگان
چکیده
The proofs and applications are based on a Riemannian version of Gromov’s non-squeezing theorem and classical integral geometry. Given a convex surface Σ ⊂ R and a point q in the unit sphere S we denote by UΣ(q) the perimeter of the orthogonal projection of Σ onto a plane perpendicular to q. We obtain a function UΣ on the sphere which is clearly continuous, even, and positive. Let us denote the minimum value for this function by uΣ. The analogue of the non-squeezing theorem we wish to present is the following result.
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