6 ms·

The thing is that subjectively "FTL" travel, a la Star Trek, is totally possible thanks to special relativity contracting distances between objects. A little m

The thing is that subjectively "FTL" travel, a la Star Trek, is totally possible thanks to special relativity contracting distances between objects. A little math shows the relative velocity in which you travel one light year measured in a rest frame, in one year in your spaceship's frame, is 70.7% of the speed of light. If you happened to be moving at the ludicrous speed of the "Oh-My-God" cosmic ray recorded in 1991, it would take you three seconds of your time to travel to the center of the galaxy. That should be good enough for anyone! https://www.fourmilab.ch/documents/OhMyGodParticle/ https://www.fourmilab.ch/documents/OhMyGodParticle/

simonh 10y ago
But length contraction means that, subjectively, you'll think you've only travelled a few hundred thousand kilometers.
- deleted 10y ago
  [deleted]
- sevenless 10y ago
  This explains the famous line from Star Wars about the Millennium Falcon "making the Kessel run in less than 12 parsecs". George Lucas was obviously hip to the implications of special relativity.
  - dec0dedab0de 10y ago
    I think the retconed explanation is that the kessel run involves going around a black hole. Bragging about parsecs is because the slower ships had to completely steer free of the blackhole, while faster ones could get closer and break free of it's gravity, thus shortening the overall distance traveled.
    - mikeash 10y ago
      I prefer the explanation that Han Solo thought they were total rubes, and gave them some nonsense just to impress them. Indeed, the fourth draft of the script has this comment after the "twelve parsecs" line: "Ben reacts to Solo's stupid attempt to impress them with obvious misinformation." The final draft says he's "obviously lying." I feel like this ridiculous retcon involving black holes, rather than sticking to the simple human explanation of braggadocio, is a microcosm of everything that subsequently went wrong with the prequels.
    - yoz-y 10y ago
      After seeing Interstellar and some Black Science Man explanations this would also mean that the fastest ships would get to the finish decades after the slow ones due to gravity shenanigans.
snarfy 10y ago
The center of the galaxy is 32,000 light years away. 32,000 years will have passed at the center of the galaxy by the time you get there in your 3.2 second journey. If you then turn around and go back, another 32,000 years will have passed before you get home. It might feel more like time travel than space travel.
- andy_ppp 10y ago
  That's why it's called space-time right...
- 3pt14159 10y ago
  This is one of my theories about why there isn't any alien life around. There is some party far in the future with a beacon or message that shouts "JOIN US HERE IN THE MIDDLE OF GALAXY R345Q2 10 BILLION YEARS IN THE FUTURE!" After about 10 thousand years of hearing the beacon and being alone we finally get restless and just build a couple thousand giant spaceships and join the rest of the universe in the most cosmopolitan place ever.
  - vslira 10y ago
    It's not a party, it's a restaurant :)
  - sevenless 10y ago
    > This is one of my theories about why there isn't any alien life around. Do we need a theory on this yet? I mean... out of all the planets we've explored reasonably thoroughly so far, 100% have had life at some point.
    - sreya 10y ago
      I've not heard that Mars had life at some point in its history. In fact I've not heard mention of any planets hosting life in their past, do you have some sources that you can point me to?
      - 10y ago
soVeryTired 10y ago
Still gonna need some inertial dampers though.
sliverstorm 10y ago
That bit about the particle is fascinating, but I am struggling to understand why a particle that travels at 0.99x of the speed of light is faster than a ship that travels at 1516x the speed of light. Is the Star Trek universe not subject to time dilation?
- grymoire1 10y ago
  The star trek universe is not subject to physics in general. Sound traveling without air, time travel, FTL, Newton's Law being ignored, Creating/destroying matter, "beaming" people down to a planet, etc.

simonh 10y ago

But length contraction means that, subjectively, you'll think you've only travelled a few hundred thousand kilometers.

deleted 10y ago
[deleted]
sevenless 10y ago
This explains the famous line from Star Wars about the Millennium Falcon "making the Kessel run in less than 12 parsecs". George Lucas was obviously hip to the implications of special relativity.
- dec0dedab0de 10y ago
  I think the retconed explanation is that the kessel run involves going around a black hole. Bragging about parsecs is because the slower ships had to completely steer free of the blackhole, while faster ones could get closer and break free of it's gravity, thus shortening the overall distance traveled.
  - mikeash 10y ago
    I prefer the explanation that Han Solo thought they were total rubes, and gave them some nonsense just to impress them. Indeed, the fourth draft of the script has this comment after the "twelve parsecs" line: "Ben reacts to Solo's stupid attempt to impress them with obvious misinformation." The final draft says he's "obviously lying." I feel like this ridiculous retcon involving black holes, rather than sticking to the simple human explanation of braggadocio, is a microcosm of everything that subsequently went wrong with the prequels.
  - yoz-y 10y ago
    After seeing Interstellar and some Black Science Man explanations this would also mean that the fastest ships would get to the finish decades after the slow ones due to gravity shenanigans.

snarfy 10y ago

The center of the galaxy is 32,000 light years away. 32,000 years will have passed at the center of the galaxy by the time you get there in your 3.2 second journey. If you then turn around and go back, another 32,000 years will have passed before you get home. It might feel more like time travel than space travel.

andy_ppp 10y ago
That's why it's called space-time right...
3pt14159 10y ago
This is one of my theories about why there isn't any alien life around. There is some party far in the future with a beacon or message that shouts "JOIN US HERE IN THE MIDDLE OF GALAXY R345Q2 10 BILLION YEARS IN THE FUTURE!" After about 10 thousand years of hearing the beacon and being alone we finally get restless and just build a couple thousand giant spaceships and join the rest of the universe in the most cosmopolitan place ever.
- vslira 10y ago
  It's not a party, it's a restaurant :)
- sevenless 10y ago
  > This is one of my theories about why there isn't any alien life around. Do we need a theory on this yet? I mean... out of all the planets we've explored reasonably thoroughly so far, 100% have had life at some point.
  - sreya 10y ago
    I've not heard that Mars had life at some point in its history. In fact I've not heard mention of any planets hosting life in their past, do you have some sources that you can point me to?
    - 10y ago

soVeryTired 10y ago

Still gonna need some inertial dampers though.

sliverstorm 10y ago

That bit about the particle is fascinating, but I am struggling to understand why a particle that travels at 0.99x of the speed of light is faster than a ship that travels at 1516x the speed of light. Is the Star Trek universe not subject to time dilation?

grymoire1 10y ago
The star trek universe is not subject to physics in general. Sound traveling without air, time travel, FTL, Newton's Law being ignored, Creating/destroying matter, "beaming" people down to a planet, etc.