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Comment Black holes can exist without a singularity (Score 4, Interesting) 356

It is generally posited that a singularity is the result of a gravitational collapse resulting in a black hole. However an event horizon will form whenever sufficient mass density occurs, thus a 'black hole'. If the contention is that the Hawking radiation dissipates the mass before the singularity forms, so be it. Does not mean no black hole, just no singularity.

I have not read the article, so I don't know if this is reflective of her contention, however:

Imagine 2 observers, 1 falling into the black hole, one with great patience a safe distance away. Over time the distant observer will see the black hole eventually become isolated and cease to accumulate new mass (trillions of years perhaps). Thereafter, Hawking radiation begins to dominate and the black hole goes on a diet, eventually going out of existence with a hot bang.

Meanwhile the more adventurous observer is falling toward the postulated center of the black hole, but is experiencing greater and greater time dilation relative to the low density external universe. Thus at some point, before reaching the singularity state, the observer 'sees' the entire future of the external universe, including an ever increasing flood of Hawking radiation that results in the black hole evaporation. So incoming matter never gets to infinite density, no singularity occurs because the evaporation happens on a different time scale than the collapse. Black hole? Yes, Singularity? No

If this is not the equivalent of the cited paper, I am free to go to Oslo at any time.

Comment Re:not true, IIRC (Score 2) 202

Let me put it in terms you can understand: If you hold a rubber band with one end in each hand, and put an ant on the rubber band at one end headed toward the other, and the ant moves at a constant rate toward your other hand, and as the ant moves you stretch the rubber band, then your hands will be further apart than the ant has moved when the ant reaches your other hand.

If you have a favorite animal, I can rephrase to accommodate.

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