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WittyUnwittingly OP t1_j27zdpk wrote

Reply to comment by Xethinus in What is our current "best guess" about how to observers that entered a black hole on opposite sides would look to each other once they crossed the event horizon? by WittyUnwittingly

>hawking radiation would annihilate anything that just passed the event horizon immediately from its own perspective

This is perhaps the most interesting point I've read all night.

Thinking about an observer's "perception" from within a black hole circles me back to all of the same problems we have with time/FTL travel, which makes sense.

An observer from "inside" a black whole should be able to perceive all of the photons arriving at the event horizon after they did simultaneously, but "infinite blue shift" should imply that any causality information would be lost (Think of a binary pulse... Physically, a 1 would be unable to arrive before a 0 or vice versa)

Yeah man... That makes total sense, because from the perspective of the observer falling in toward the black hole, they would arrive at the singularity at the same instant that it evaporates due to hawking radiation at the end of the universe. This fits very neatly with some of the other "causality protection" conjectures.

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Xethinus t1_j2806q2 wrote

Oh. If you keep my amateur theory consistent, there is no actual singularity. Any nothing would ever approach it.

To the observer, all of this happens at the same time, while they pass the event horizon. The center of the black hole would take an infinite amount of time to approach.

Black holes are really annoying, because most of their calculations result in "undefined" or "zero" and there's not much in between.

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WittyUnwittingly OP t1_j280ddz wrote

Well, you can use the word "annoying" if you'd like, but I would call it a rather elegant reconciliation of a lot of the problems I was having.

For example, if one were to have a mastery of mechanics such that they could dip in and out of an event horizon, how could there be any continuity of what they perceived versus what they did? No need for any of that with this explanation, because it necessarily cannot happen.

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superVanV1 t1_j2952g4 wrote

not unless we achieve FTL travel.
though under current models of acheiving that via the warping of space, sticking a spacetime bubble into a spacetime singularity may cause "issues"

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WittyUnwittingly OP t1_j29s599 wrote

Well, even if you took an Alcubierre drive into a singularity, once you get there, there would be no path you could choose to get back out, regardless of what speed you can go. Even if you could somehow distort space enough to "get back," when would you arrive? At the end of the universe?

Seems like your best bet for something that can go into and come out of blackhole, is something that does not obey the normal laws of causality, and can come out of a black hole before it goes in.

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superVanV1 t1_j2a3qxv wrote

Which we have no way to model for, since current mathematics still just returns a big ‘ol error sign when trying to calculate beyond the event horizon. It’s entirely possible that physics just.ceases to operate properly at that point

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Kevskates t1_j2c1vse wrote

All this talk of the limits of physics make me feel like we’re in a video game trying to explain the invisible edge of the map

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paloprint t1_j2cbew3 wrote

Like when McConaughey touched hands with Brand. Corny I know. He’s was going out they were going in.

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wokeupatapicnic t1_j2brwdu wrote

Pretty sure you just described the Firewall theory. I think Hawking proved that or at least was able to suggest that, this is not the case, but it’s worth looking into on your own if you’re interested!

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