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Miklós Schweitzer 2004, Problem 7

Source: Miklós Schweitzer 2004

July 30, 2016
college contestsMiklos Schweitzer3D geometryspherepolynomialtopologygeometry

Problem Statement

Suppose that the closed subset KK of the sphere S2={(x,y,z)R3 ⁣:x2+y2+z2=1}S^2=\{ (x,y,z)\in \mathbb{R}^3\colon x^2+y^2+z^2=1 \} is symmetric with respect to the origin and separates any two antipodal points in S2\KS^2 \backslash K. Prove that for any positive ε\varepsilon there exists a homogeneous polynomial PP of odd degree such that the Hausdorff distance between Z(P)={(x,y,z)S2 ⁣:P(x,y,z)=0}Z(P)=\{ (x,y,z)\in S^2 \colon P(x,y,z)=0\} and KK is less than ε\varepsilon.