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Aseyhe t1_jdikry0 wrote

Reply to comment by PogTuber in Could a black hole just be a big neutron star that just has gravity so high light cant escape? by SlyusHwanus

Anything inside the event horizon must reach the singularity in finite proper time (that is, time from its own point of view). However, events inside the horizon can never be in the (causal) past of an outside observer, so there is never a time at which an outside observer could say objectively that the neutron star is no longer there. Maybe that's what the claim was?

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PogTuber t1_jdiypvx wrote

No the claim was that the victim would collide with the neutron star, assuming they weren't ripped to shreds. Basically all matter would join what was left of the star.

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PlaidBastard t1_jdj0kpn wrote

That's more like saying relativistic effects mean that any matter that fell in less than infinity years before you is going to be between you and the actual singularity. It's not that the neutron star is 'in' there, it's that it can't ever finish falling in before you catch up with it's trailing edge...I think?

Kinda way out on a limb there. Can anyone help out if that's totally wrong?

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Not_Pictured t1_jdj9ate wrote

The singularity is a finite distance from the event horizon which means it's a finite time away (as measured in both time and space and the distinction could matter in this case) when inside the event horizon. You will catch up to something and that something should be a singularity.

The acceleration felt by the atoms or neutrons in a neutron star is > the speed of light. Nothing can resist ending up in the infinitely dense center. There is no physical mechanism we know of that could resist it.

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PlaidBastard t1_jdj9ttv wrote

So, really, you're one layer of an infinite relativistic spacetime-baklava of matter approaching the singularity...

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Not_Pictured t1_jdjal7z wrote

I guess. The mathematical models we are using to guess at what is going on already break with what we've got.

Really as someone who intends to never enter an event horizon, mathematically there is no difference between the matter of a black hole being in a singularity, or being evenly spread just under the event horizon. The stuff that comes out of a black hole, gravity and charge, don't care so in a very real sense there isn't a difference.

In fact it might not even be defined in the same sense that many things in quantum mechanics aren't defined until measured. And since it can't be measured as far as the external universe is concerned, why would reality care to pick?

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