4 ms·

Not sure if it matters too much from an individualistic perspective. Near light-speed travel will allow a person to go anywhere instantaneously, they'd just hav

Not sure if it matters too much from an individualistic perspective. Near light-speed travel will allow a person to go anywhere instantaneously, they'd just have to contend with leaving the time and space they know behind them.

amelius 5y ago
> Near light-speed travel will allow a person to go anywhere instantaneously Only if you ignore the enormous acceleration/deceleration forces needed for this.
- cedricd 5y ago
  Surprisingly it's not that much. At a constant 1G acceleration you could travel across the galaxy (100k light years) in 12 years (from your reference frame)[0]. I definitely agree that such travel would require enormous amounts of energy. [0]: https://en.wikipedia.org/wiki/Space_travel_under_constant_acceleration https://en.wikipedia.org/wiki/Space_travel_under_constant_ac...
- sgjohnson 5y ago
  also, "instantaneously" is a stretch on a galactic scale. 299792000 m/s isn't as fast as it sounds if you need to cross the entire galaxy. Time dilation doesn't matter here.
mulmen 5y ago
Only for sufficiently small values of anywhere. Even near-light-speed communication in fiber optics has detectable and significant delay just in crossing a continent. A trip made physically by humans every day. Near-light-speed travel to the Moon would take a few seconds. Near-light-speed travel to Mars would take longer than my drive to the grocery store. These are not "instantaneously."
- krapp 5y ago
  OK. Only Pluto in a few hours, Mars in a few minutes, and the moon in less time it would take for me to reach the toilet from my living room. Not literally instantaneous, but still practically instantaneous at the scale of the solar system.
- teaearlgraycold 5y ago
  I'm talking about time dilation. From the perspective of the pilot of a near light speed ship a trip across the galaxy would be instantaneous.
  - psyc 5y ago
    It's instantaneous at 100% of light speed (impossible for massive objects). At "near" light speed, you need seventeen nines (0.99999999999999999c) to bring a trip across the galaxy down to a subjective day. I'm not sure how near your idea of "near" is. You also need instantaneous acceleration at both ends, which is quite a requirement.

amelius 5y ago

> Near light-speed travel will allow a person to go anywhere instantaneously Only if you ignore the enormous acceleration/deceleration forces needed for this.

cedricd 5y ago
Surprisingly it's not that much. At a constant 1G acceleration you could travel across the galaxy (100k light years) in 12 years (from your reference frame)[0]. I definitely agree that such travel would require enormous amounts of energy. [0]: https://en.wikipedia.org/wiki/Space_travel_under_constant_acceleration https://en.wikipedia.org/wiki/Space_travel_under_constant_ac...
sgjohnson 5y ago
also, "instantaneously" is a stretch on a galactic scale. 299792000 m/s isn't as fast as it sounds if you need to cross the entire galaxy. Time dilation doesn't matter here.

mulmen 5y ago

Only for sufficiently small values of anywhere. Even near-light-speed communication in fiber optics has detectable and significant delay just in crossing a continent. A trip made physically by humans every day. Near-light-speed travel to the Moon would take a few seconds. Near-light-speed travel to Mars would take longer than my drive to the grocery store. These are not "instantaneously."

krapp 5y ago
OK. Only Pluto in a few hours, Mars in a few minutes, and the moon in less time it would take for me to reach the toilet from my living room. Not literally instantaneous, but still practically instantaneous at the scale of the solar system.
teaearlgraycold 5y ago
I'm talking about time dilation. From the perspective of the pilot of a near light speed ship a trip across the galaxy would be instantaneous.
- psyc 5y ago
  It's instantaneous at 100% of light speed (impossible for massive objects). At "near" light speed, you need seventeen nines (0.99999999999999999c) to bring a trip across the galaxy down to a subjective day. I'm not sure how near your idea of "near" is. You also need instantaneous acceleration at both ends, which is quite a requirement.