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Is Faster-Than-Light Travel or Communication Possible? (1997)

math.ucr.edu

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Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#11

Post by [deleted] »

simonh wrote: post #9
sevenless wrote: post #7

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 199…

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

[deleted]

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#12

Post by snarfy »

sevenless wrote: post #7

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 199…

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.

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#13

Post by soVeryTired »

sevenless wrote: post #7

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 199…

Still gonna need some inertial dampers though.

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#14

Post by sevenless »

simonh wrote: post #9
sevenless wrote: post #7

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 199…

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

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.

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#16

Post by aaron695 »

Thinking you can go faster than light for communication is the same as believing perpetual motion or even being a flat earther.

You can't do it, there are no hacks to do it. It's a law of the universe. No matter how many SciFi movies tell you other wise.

I just don't get the acceptance of this anti-scientific concept.

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#17

Post by jandrese »

aaron695 wrote: post #16

Thinking you can go faster than light for communication is the same as believing perpetual motion or even being a flat earther. You can't do it, there are no hacks to do it. It's a law of the universe. No matter how many SciFi movies tell you other wise. I just don't get the acceptance of this anti-scientific concept.

This is exactly right given our current understanding of the universe. FTL travel violates causality, which is a fundamental principle of the universe.

I wouldn't go quite so far as to say it's totally impossible though. There is a whole lot about the universe we don't understand and I can't rule out the possibility that there are entire branches of mathematics and physics that we don't know about.

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#18

Post by dec0dedab0de »

sevenless wrote: post #14
simonh wrote: post #9

Earlier quoted context omitted.

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

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.

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.

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#19

Post by lisivka »

aaron695 wrote: post #16

Thinking you can go faster than light for communication is the same as believing perpetual motion or even being a flat earther. You can't do it, there are no hacks to do it. It's a law of the universe. No matter how many SciFi movies tell you other wise. I just don't get the acceptance of this anti-scientific concept.

But some objects in space are already moving faster than speed of light in vacuum. [1]

[1] https://www.youtube.com/watch?v=RaELad94KZs

Re: Is Faster-Than-Light Travel or Communication Possible? (1997)

#20

Post by andy_ppp »

snarfy wrote: post #12
sevenless wrote: post #7

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 199…

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.

That's why it's called space-time right...
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