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A mechanical model that exhibits a gravitational critical radius

Kirk T. McDonald
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Abstract

Circular orbits of a particle sliding on a frictionless surface of revolution about a vertical axis are unstable below a critical radius if the curvature of the surface satisfies a specified condition. This behavior can be realized in a mechanical model, which give a glimpse of the greater complexity of particle orbits in curved rather than flat spacetime.

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Kirk T. McDonald. 2000-06-29. A mechanical model that exhibits a gravitational critical radius. https://doi.org/10.1119/1.1351152

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