If a large (>1.5 SM) conventional star collapses to become a black hole, textbooks say that a singularity will form in the BH. A singularity is characterized by a gravitational field of infinite potential. (Or infinite spacetime curvature if you prefer that terminology).(adsbygoogle = window.adsbygoogle || []).push({});

1. As I understand it, a BH singularity does not possess infinite mass. It possess only the total mass of the original particles that collapsed to form it. Correct?

2. If the gravitational field is "infinite" at the "edge" of the singularity, how far must one be away from that edge for the gravitational field to be finite? In other words, is there a definition of the exact physical extent of the "infinite" singularity part of the BH? Is the boundary between infinite and finite gravitation zones in the BH crisp or indefinite? How can the potential of a gravitational field transition between infinite and finite merely as a consequence of a fairly small spatial relocation?

3. Assuming a BH singularity causes an infinite gravitational field (within it), it seems that the "infinite" gravitational energy is larger than the "finite" gravitational energy possessed by the star before its collapse. How is it possible for an object of finite mass (star) to increase its total gravitational energy from finite to infinite (by collapsing to a BH) without violating the conservation of energy? As I understand it, the "relativistic rest mass" of an object is equal to the rest mass of the individual particles that have collapsed together to form the object, minus the binding energy that would be needed to pull the particles back apart. The subtraction is called the "mass defect." Perhaps the answer to this question is that the infinite gravitational binding energy of the singularity should be subtracted from its infinite gravitational mass-energy, to yield a finite "net relativistic mass-energy?" I haven't seen it described this way so I would appreciate some help.

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# Black Hole Singularities

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