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There are many thought experiments about what it would be like to fall into a black hole, spaghettififaction, the singularity at the center and so on. But to me it seems that no object could actually get to a point where spaghettification starts to happen.

Practically, unless the lifespan of a black hole (and the universe it is contained in) was infinite, could anything ever even penetrate the event horizon, given that time dilation factor at the event horizon as seen from an outside observer approaches infinity?

I understand that subjectively an observer falling towards a black hole won't see the event horizon at the location an outside observer sees it. However, from the outside perspective of the universe, the time passage of an object approaching the event horizon approaches zero.

Now, the important part is that black holes do not exist forever, they evaporate eventually due to Hawking radiation.

Since black holes will evaporate eventually, doesn't that mean that from an outside perspective the object will just hang right outside the event horizon and will only get closer to the center as the black hole finally evaporates (getting arbitrarily close to the event horizon but never beyond)?

That in turn would mean for the local experience of the observer falling towards the black hole, that the black hole will basically evaporate in front of you as you fall towards it, with spaghettification never happening (but likely your body being eaten away by the anti-matter particles of Hawking radiation).

If that logic is sound, then that would also mean that there is no singularity at the center of a black hole but that instead all the energy is compressed into a 2 dimensional surface located at the event horizon (as seen from the outside).

I assume my logic or understanding is flawed, I'd like to understand what exactly I got wrong.

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  • $\begingroup$ That is an important observation. From the standpoint of all observers outside the black hole, nothing ever does cross the horizon. It all just gets very close and then fades away. The term "event horizon" means that the black hole is the collection of events that outside observers agree do not happen. $\endgroup$
    – RC_23
    May 19, 2022 at 15:25
  • $\begingroup$ @RC_23 but since black holes evaporate within finite time, that should also hold true for the local observer falling towards the black hole. No? $\endgroup$ May 19, 2022 at 15:27
  • $\begingroup$ For a "Local observer falling" meaning a freefalling observer on a geodesic, no. This observer does not see the horizon, and does not see Hawking Radiation. Both of those phenomena are frame dependent. An observer near the horizon firing rockets to stay outside (i.e. stationary with respect to an observer far away) will see both the horizon and hawking radiation. $\endgroup$
    – RC_23
    May 19, 2022 at 15:33
  • $\begingroup$ @safesphere so am I right to assume, that the local observer would not experience spaghettification, but rather being evaporated by anti-matter particles? $\endgroup$ May 25, 2022 at 19:11

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