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As I understand, to an observer well outside a black hole, anything going towards it will appear to slow down, and eventually come to a halt, never even touching the event horizon.

What happens if you (theoretically) wait long enough? Would you see the black hole vaporize before you see the object even reach it?

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Related: physics.stackexchange.com/q/21319/2451 and links therein. –  Qmechanic Nov 2 '13 at 1:21
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up vote 1 down vote accepted

Realistically, because the light emitted from the infalling object is quantized, you will observe the "last" photon emitted from the infalling object in (very much) finite time.

If you keep waiting after that, you will eventually observe the black hole Hawking-radiate away, and any "information" carried by the infalling object will be "encoded" in the Hawking radiation.

Here's an additional argument:

When the infalling object passes through the event horizon, it will contribute to the mass of the black hole, which will cause the event horizon to expand outward even more. This ensures even further that the infalling object will no longer be observable from the outside in a relatively short time, compared with the lifetime of the black hole.

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