Definition of a Point Mass

Every point mass has a Schwarzchild radius:

pointmass

For theoretical purposes, in using point masses to calculate gravitational fields, a surface is calculated equal to the Schwarzchild radius. Every mass, or collection of particles, if reduced to a point would be contained by this surface. The surface derived classically in General Relativity is static and isotropic; in reality, the surface may not necessarily be either:

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