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> As you fall from the event horizon to the singularity, you see the entire future of the universe unfold No, you don't. Most of the universe will never be in

by pdonis 6y ago

> As you fall from the event horizon to the singularity, you see the entire future of the universe unfold No, you don't. Most of the universe will never be in your past light cone as you fall to the singularity. The fact that the singularity is unavoidably in your future when you are inside the hole, does not mean it is also to the future of everything outside the hole.

lostmsu 6y ago
This is unnecessarily pedantic. What parent meant is more akin to "if Earth would exist forever, and you would live forever on it, you'd see the entire future of the universe unfold". Obviously you won't see what happens on the moon when it is behind the horizon, but that was not the point.
- pdonis 6y ago
  > What parent meant is more akin to "if Earth would exist forever, and you would live forever on it, you'd see the entire future of the universe unfold". No, that's not what the post I responded to meant. That post was specifically talking about what an observer falling into a black hole and hitting the singularity would see. That is not the same as existing forever outside the hole's horizon.
  - lostmsu 6y ago
    Why do you think the post did not refer to its author's understanding, that your experience would be the same as hanging forever just outside the horizon except in finite time from your perspective? This would be my default interpretation of their comment, and since you are successfully attacking a different stronger interpretation you should reconsider that this strong interpretation is the right way to interpret the comment. That's scenario is actually covered in HN discussion rules. To be fair until your comment I wrongly believed the moment you'd be crossing horizon you'd be hit by all light ever emitted toward that point of the horizon in the entirety of the future (assuming no hawking radiation of course).
hnews_account_1 6y ago
It's basically all the future events that happen inside the black hole isn't it? At least that's what I meant.
- pdonis 6y ago
  > It's basically all the future events that happen inside the black hole isn't it? No, you won't even see all of those if you fall in; the most you will see are the events that end up in your past light cone before you hit the singularity. That is only a portion of the entire spacetime region inside the horizon.

by pdonis 6y ago

lostmsu 6y ago

This is unnecessarily pedantic. What parent meant is more akin to "if Earth would exist forever, and you would live forever on it, you'd see the entire future of the universe unfold". Obviously you won't see what happens on the moon when it is behind the horizon, but that was not the point.

pdonis 6y ago
> What parent meant is more akin to "if Earth would exist forever, and you would live forever on it, you'd see the entire future of the universe unfold". No, that's not what the post I responded to meant. That post was specifically talking about what an observer falling into a black hole and hitting the singularity would see. That is not the same as existing forever outside the hole's horizon.
- lostmsu 6y ago
  Why do you think the post did not refer to its author's understanding, that your experience would be the same as hanging forever just outside the horizon except in finite time from your perspective? This would be my default interpretation of their comment, and since you are successfully attacking a different stronger interpretation you should reconsider that this strong interpretation is the right way to interpret the comment. That's scenario is actually covered in HN discussion rules. To be fair until your comment I wrongly believed the moment you'd be crossing horizon you'd be hit by all light ever emitted toward that point of the horizon in the entirety of the future (assuming no hawking radiation of course).

hnews_account_1 6y ago

It's basically all the future events that happen inside the black hole isn't it? At least that's what I meant.

pdonis 6y ago
> It's basically all the future events that happen inside the black hole isn't it? No, you won't even see all of those if you fall in; the most you will see are the events that end up in your past light cone before you hit the singularity. That is only a portion of the entire spacetime region inside the horizon.