【摘 要】
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The Christoffel problem is equivalent to the existence of convex solutions to the Laplace equation on the unit sphere Sn.Necessary and sufficient conditions have been found by Firey(1967)and Berg(1969),by using the Green function of the Laplacian on the s
【机 构】
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School of Mathematical Sciences,Zhejiang University,Hangzhou 310027,China;Centre for Mathematics and
论文部分内容阅读
The Christoffel problem is equivalent to the existence of convex solutions to the Laplace equation on the unit sphere Sn.Necessary and sufficient conditions have been found by Firey(1967)and Berg(1969),by using the Green function of the Laplacian on the sphere.Expressing the Christoffel problem as the Laplace equation on the entire space Rn+1,we observe that the second derivatives of the solution can be given by the fundamental solutions of the Laplace equation.Therefore we find new and simpler necessary and sufficient conditions for the solvability of the Christoffel problem.We also study the Lp extension of the Christoffel problem and provide sufficient conditions for the problem,for the case p≥2.
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