Would you outlive everyone?

I'm coming from the point of view that time would be experienced more slowly (although not from your point of view) the denser the gravity gets.

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    $\begingroup$ You would observe the universe to age rapidly behind you, but your lifetime as you experienced it would be strongly curtailed. $\endgroup$ – dmckee --- ex-moderator kitten Aug 31 '13 at 23:28
  • $\begingroup$ Yes! Simply, yes! $\endgroup$ – Cheeku Aug 31 '13 at 23:35

As you approach the event horizon, the Doppler shift of any electromagnetic signals you send back out approaches infinity. Any distant observer will get old and die while monitoring your signals that get slooower and sloooooower.

Your own experience is that you exist for some finite time (not very long, for a black hole of a typical size), and then you hit the singularity and die. (You may die earlier because of tidal forces. That depends on the size of the black hole.)

To you, the experience is that the Doppler shifts of signals coming in from the outside become greater and greater. However, you don't get to see the arbitrarily distant future of the outside universe. For any location outside the event horizon, there is some latest time at which their signals can reach you before you go splat into the event horizon.

I've never liked descriptions of this sort of thing that use phrases like "it seems to you like" or "you see" or "in your frame of reference." General relativity doesn't have global frames of reference. It's meaningless to talk about whether something far away is happening "now" as judged "according to you." All you can do is receive or transmit signals. You know they're just signals. BTW, there's a classic science fiction novel, Gateway, by Frederik Pohl, in which the protagonist makes himself really, really miserable by imagining that his lover, whom he abandoned to fall into a black hole, is forever cursing him "now." A better understanding of general relativity would have been the best therapy for the poor guy -- but I guess that would have spoiled the book.

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    $\begingroup$ "and then you hit the event horizon and die": has the transition from classical GR to firewalls officially happened? $\endgroup$ – user10851 Sep 1 '13 at 4:05
  • $\begingroup$ If you are a free falling observer which falls into a big black hole (neglectible tidal forces), nothing happens at you when you cross the horizon. The firewall AMPS folks are getting more and more alone, thanks to Maldacena, Sussinking, Van Raamsdonk, etc... $\endgroup$ – Trimok Sep 1 '13 at 13:55
  • $\begingroup$ @ChrisWhite: Oops, thanks for the correction. Obviously that should have been "singularity." $\endgroup$ – Ben Crowell Sep 1 '13 at 14:10

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