Time dilation near a black hole caused by relativistic speed or extreme gravity?

[K^2]

Correction, from perspective of the ship, time flows normally. The reason the ship's computer would have trouble responding is because due to space contraction, the distance between origin and destination is effectively zero. Of course, that gives you the same result. Voyage time is effectively zero. But getting up to light speed in finite speed also requires infinite acceleration. So any interstellar mission is going to be acceleration-limited, even if you somehow found a way to provide all of the required energy.

[Starwhip]

Hmm. So, you're saying that at lightspeed (if you got there) the universe would be going by infinitely fast? Interesting.

[WestAir]

At lightspeed would you ever leave the visible Universe, or is the fact that space is expanding faster than C enough to stop you from physically being able to journey outside of our visible Universe?

If yes, does that mean that travel at C would screw things up because while you can get anywhere in zero time, there are still places that exist that are beyond a sort of "white hole" barrier?

[K^2]

That's actually a very good question. Just because something is receding from you faster than light, doesn't mean you can't catch up to it by moving at sub-light speeds. Because, assuming uniform rate of expansion, as you make your way towards the remote object, it would appear to slow down. You might just be able to catch up with some such objects. It's all going to depend on rate of acceleration of the expansion. And I honestly don't know if there is a way to go past visible universe or not without means of FTL travel. If I can find a reasonable approximation of the Universe's metric, I might be able to do some computations to find out, but I wouldn't know where to start without it. I can ask around.

[WestAir]

K^2, that would be awesome if you could figure it out. From my (limited) perspective it almost seems like the expansion is a natural means to counter any object from "leaving" its visible Universe via any acceleration, up to and including photons.

[HeadHunter67]

due to space contraction, the distance between origin and destination is effectively zero. Voyage time is effectively zero. But getting up to light speed in finite speed also requires infinite acceleration.

Hmm. So, you're saying that at lightspeed (if you got there) the universe would be going by infinitely fast?

This is basically what I was trying to illustrate before. Because time simply would not appear to pass for someone travelling at c, they would appear to travel an infinite distance instantly. But as K^2 said, that would require infinite acceleration, which is impossible in a finite space for the same reason that one cannot travel an infinite distance instantly:

Because distance (and velocity) is measured between two fixed points, it cannot be measured subjectively. A second point of observation is required. Therefore, perceived speed may be relative, but distance is absolute.