An observer is firing his rockets in order to hover over a black hole event horizon. With his super-infrared vision, he sees all the mass of the black hole "frozen" in slow time just above the event horizon. Then he briefly cuts off his rockets so that he is in free-fall. In the free-falling frame, he sees no event horizon. By the conventional internet wisdom, he very quickly sees all the mass of the black hole black-out as it actually crosses the Schwarzchild radius. Then before he himself crosses the radius, he turns on his rockets, so he is once again somewhere above the event horizon. Now what does he see? A black hole with all the mass inside the event horizon? That's not supposed to happen in finite time.(adsbygoogle = window.adsbygoogle || []).push({});

Resolution of the paradox:

When the observer cut off his rockets, he did not see the black hole mass crossing the Schwarzchild radius. Instead he saw all the mass already well past the radius and already clustering around the singularity, where it's "frozen" by the higher gravity there . When he turned his rockets back on, he saw the same mass "frozen" near the event horizon. The event horizon IS the singularity -- as viewed from a different reference frame.

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# Black Hole Paradox?

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