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This question was bugging me for many years. Here it was argued that it would take an infinite time for somebody (suppose, an astronaut) to fall into the black hole, given that it is not his time, but the time at spatial infinity (suppose it is the time on the space station). I completely agree with this result.

Now to my question. Forget about the astronaut for a moment, let's focus on the process from the point of view of the person on the space station. Imagine him immortal. Then he will live long enough for the black hole to evaporate due to the Hawking effect. But the astronaut wouldn't reach the event horizon by that point (it is taking infinitely long for him to do so). So after all he will be killed by a flash of light/particles before falling inside the black hole.

Because all frames of reference are good to go, this also holds in the frame of the astronaut. He will not experience 'nothing' when falling into the black hole. Instead, he will almost instantly (his clocks are ticking much slower) be evaporated by the Hawking radiation. Right?

There are another likely scenarios of the end of the outside world (like thermal death) which would take finitely long of the space station time. They would also destroy the astronaut before he crosses the event horizon.

It seems like these arguments also prohibit any matter to be sucked inside the event horizon. Black holes then have no horizons, they are just very dense formations of matter with scales very close to the black hole diameter, but yet larger.

What is wrong in my propositions? After all, it is commonly believed that black holes suck in the neighbouring matter.

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  • $\begingroup$ Wow, thanks. I didn't see that question in the 'possible duplicates' list. It is really a duplicate, so this question can be closed. Thanks again. $\endgroup$ Commented Nov 10, 2014 at 0:09
  • $\begingroup$ I am not sure they really answer your question there, I think I read that somewhere else, but I cannot make sense of it now (I don't know how to unflag!). $\endgroup$
    – user65081
    Commented Nov 10, 2014 at 0:21
  • $\begingroup$ You have the argument back to front. It would take an infinite time for an external observer but, for the point of view of the victim, it would happen in real time. Depending on the size of the BH, he might be spaghettified very rapidly or, in the case of a supermassive BH, he might go right through the event horizon without noticing anything amiss. $\endgroup$
    – hdhondt
    Commented Nov 10, 2014 at 0:39
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    $\begingroup$ @hdhondt but from an outside point of view, how can you see the black hole is increasing its mass if you cannot "see" anything entering into it. Does the black hole mass/event horizon size ever grow for an external observer? $\endgroup$
    – user65081
    Commented Nov 10, 2014 at 0:44
  • $\begingroup$ Related: physics.stackexchange.com/q/82678/2451 $\endgroup$
    – Qmechanic
    Commented Nov 10, 2014 at 0:44

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