The Hessian of the Distance from a Surface in the Heisenberg Group
نویسندگان
چکیده
Given a smooth surface S in the Heisenberg group, we compute the Hessian of the function measuring the Carnot-Charathéodory distance from S in terms of the Mean Curvature of S and of an “imaginary curvature” which was introduced in [2] in order to find the geodesics which are metrically normal to S. Explicit formulae are given when S is a plane or the metric sphere.
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