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It’d be fun to live on a planet around one of these stars. Life would be normal for you. But the rest of the universe would be running on fast forward. Maybe

It’d be fun to live on a planet around one of these stars. Life would be normal for you. But the rest of the universe would be running on fast forward. Maybe a civilization could use these stars to spread itself to other parts of the galaxy or, if fast enough, to other galaxies.

vermilingua 6y ago
Even better, half the universe would be in fast forward, everything behind you in slow motion! Watching a galaxy collission in accelerated time and a supernova in slowmo would be a unique experience.
- dnadler 6y ago
  I don't believe this is the case, I think you may be confusing the effects of time dilation and redshift.
  - deleted 6y ago
    [deleted]
- p1mrx 6y ago
  Some events would appear faster because you're moving toward them, but once you account for that, all other clocks in the universe would tick slower from your perspective.
- MichaelApproved 6y ago
  Time dilation isn’t dramatic as you might think. For example, at 66% the speed of light, you only get a 1.3 (or 30%) time difference. You have to get into the 90% range for something meaningful. Even at 96% the speed of light, it’s a 4x speed difference. 99.99% is 80x time difference. 99.999% is 240x time diff. To have time speed up to the point of civilizations rising and falling in a matter of days, you’d need to be traveling at 99% (with a few 9s in the decimal places). Though at relative speeds that high, it would be difficult to actually see what’s happening. Here’s a calculator that’ll show you time dilation at different speeds https://keisan.casio.com/exec/system/1224059993 https://keisan.casio.com/exec/system/1224059993
  - moralestapia 6y ago
    From the site you linked: >Purpose of use: In my Air Force career flying for over 21 years, curious as to how much I actually aged. Nice use case :D
BurningFrog 6y ago
I fear that it would be like sticking your head out the window for a cross country car trip. You see a lot, but your face would be caked over with bugs. IOW, a planet like that would have a much larger chance of colliding with interstellar debris. Then again, there is probably very little of that.
- ganafagol 6y ago
  Tried this recently? Bug density is declining dramatically.
wruza 6y ago
But why fast forward? Doesn’t SR predict slower perceived time for objects moving relative to the observer?
- taneq 6y ago
  Depends on direction.
  - ganafagol 6y ago
    That's not how special relativity works. You may be confusing it with red shift.
    - taneq 6y ago
      Yeah that was just a brain fart. Mea culpa.
- divbzero 6y ago
  Yes, I think you are right to question whether they would observe the rest of the universe running in fast forward. If a hypervelocity star passed by us, we would see them in slow motion because they are moving at high speed relative to us. At the same time, they would see us in slow motion because we would be moving at high speed relative to them. The effect of “the other clock is slower” is reciprocal. The weirder and non-reciprocal effects would occur when the hypervelocity star is first slingshotted out to high speed. At that point they would be close to a black hole (deep in a gravitational well) and accelerating (non-inertial frame of reference). Under those conditions, their clock would run slower than our clock for observers on both sides — i.e., we would see them in slow motion and they would see us in fast forward.
quotemstr 6y ago
You'd have no hope of ever exploring that universe though. Decelerating from 0.5c isn't really practical with any technology that we're pretty sure actually works. Sure, you'd see the rest of the universe on fast-forward, but you'd never be able to leave your own solar system.
Apofis 6y ago
I don't think life would be that normal on a 99.96% light-speed travelling shattered nebula plasma star thing...

vermilingua 6y ago

Even better, half the universe would be in fast forward, everything behind you in slow motion! Watching a galaxy collission in accelerated time and a supernova in slowmo would be a unique experience.

dnadler 6y ago
I don't believe this is the case, I think you may be confusing the effects of time dilation and redshift.
- deleted 6y ago
  [deleted]
p1mrx 6y ago
Some events would appear faster because you're moving toward them, but once you account for that, all other clocks in the universe would tick slower from your perspective.
MichaelApproved 6y ago
Time dilation isn’t dramatic as you might think. For example, at 66% the speed of light, you only get a 1.3 (or 30%) time difference. You have to get into the 90% range for something meaningful. Even at 96% the speed of light, it’s a 4x speed difference. 99.99% is 80x time difference. 99.999% is 240x time diff. To have time speed up to the point of civilizations rising and falling in a matter of days, you’d need to be traveling at 99% (with a few 9s in the decimal places). Though at relative speeds that high, it would be difficult to actually see what’s happening. Here’s a calculator that’ll show you time dilation at different speeds https://keisan.casio.com/exec/system/1224059993 https://keisan.casio.com/exec/system/1224059993
- moralestapia 6y ago
  From the site you linked: >Purpose of use: In my Air Force career flying for over 21 years, curious as to how much I actually aged. Nice use case :D

BurningFrog 6y ago

I fear that it would be like sticking your head out the window for a cross country car trip. You see a lot, but your face would be caked over with bugs. IOW, a planet like that would have a much larger chance of colliding with interstellar debris. Then again, there is probably very little of that.

ganafagol 6y ago
Tried this recently? Bug density is declining dramatically.

wruza 6y ago

But why fast forward? Doesn’t SR predict slower perceived time for objects moving relative to the observer?

taneq 6y ago
Depends on direction.
- ganafagol 6y ago
  That's not how special relativity works. You may be confusing it with red shift.
  - taneq 6y ago
    Yeah that was just a brain fart. Mea culpa.
divbzero 6y ago
Yes, I think you are right to question whether they would observe the rest of the universe running in fast forward. If a hypervelocity star passed by us, we would see them in slow motion because they are moving at high speed relative to us. At the same time, they would see us in slow motion because we would be moving at high speed relative to them. The effect of “the other clock is slower” is reciprocal. The weirder and non-reciprocal effects would occur when the hypervelocity star is first slingshotted out to high speed. At that point they would be close to a black hole (deep in a gravitational well) and accelerating (non-inertial frame of reference). Under those conditions, their clock would run slower than our clock for observers on both sides — i.e., we would see them in slow motion and they would see us in fast forward.

quotemstr 6y ago

You'd have no hope of ever exploring that universe though. Decelerating from 0.5c isn't really practical with any technology that we're pretty sure actually works. Sure, you'd see the rest of the universe on fast-forward, but you'd never be able to leave your own solar system.

Apofis 6y ago

I don't think life would be that normal on a 99.96% light-speed travelling shattered nebula plasma star thing...