English: A planet consists of a large but very thin ultra-dense disk that generates earthlike gravity. The planet is restricted lie within the plane, y = 0, using the non-Euclidean coordinates of linearized General Relativity. The metric is such that inhabitants on each side would perceive their
world to be bowl shaped. Light follows path (a) and (b) represents a straight line that has a complicated equation y=f(x) because the (x,y) coordinate system is not Cartesian.
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