protip: ET is already here.
Breaking the warp barrier for faster-than-light travel
21–30 of 76 posts
Re: Breaking the warp barrier for faster-than-light travel
#22We don’t need hyperexotic negative energy to travel to the stars, we just need to live a lot longer, and we need our friends and family to live longer too so we can comeback and see them again.
Living longer would help. Changing society would help more. If you can engineer society towards some obsession with expanding through the universe, we could probably travel to the stars in our lifetimes. It'll be slow, shitty, dangerous travel though.
Re: Breaking the warp barrier for faster-than-light travel
#23I am not a physicist by any means, so this may come off as a dumb question, but: If gravity waves have been discovered, and they move at the speed of light (speed of causality?), being thrown off by the most energetic events in the universe, how can something like an Alcubierre drive even work when essentially it is also a gravitational wave generated by far less energy?
Re: Breaking the warp barrier for faster-than-light travel
#24We don’t need hyperexotic negative energy to travel to the stars, we just need to live a lot longer, and we need our friends and family to live longer too so we can comeback and see them again.
I agree but the nearest star is (only?) 4 light years away. If we only managed to travel close to the speed of light, we surely live long enough today. Time dilation will cause our friends to be older by a few years than they should be, but not by that much right?
There is a cool calculator of what happen if you travel around with constant 1G acceleration.
Long story short: to travel to Alpha Centauri it would take for the traveller still about 4 years, and when back at home, people would have aged only some months more than the astronauts.
Crazy things happen if you decide to go on galaxy-wide trips though, to the astronauts because space contraction they perceive their own trip as happening still rather quick, a 100 000 ly trip (the size of our galaxy, for reference) takes 22 years for someone inside a spaceship with 1g acceleration, perfectly doable. But people outside still see it taking 100 000 years... (meaning they will be 100 000 years "older" from the point of view of the astronauts)
After I found all this out, I concluded space travel isn't THAT hard, assuming you have a way to accelerate constantly at 1g for 22 years (that is the hardest part actually), you can get anywhere in the galaxy in a human lifetime, no need for generation ships, cryogenics or other crazy tech.
In fact even going to other galaxies is easy, a trip to Andromeda takes 28 years!
Mind you, all those calculations were done assuming you will burn at 1g until half the distance, and then burn at 1g to brake, if you don't brake you can get even faster to places (although that wouldn't be very useful I guess).
According to google the universe is 93 billion ly wide. If you accelerate (and decelerate later) at constant 1g, this trip takes 49 years for the astronaut!
Re: Breaking the warp barrier for faster-than-light travel
#25It is early in the morning, so I'm still irritable, but this line is pretty egregious -- The energy savings would need to be drastic, of approximately 30 orders of magnitude to be in range of modern nuclear fission reactors.” He goes on to say: “Fortunately, several energy-saving mechanisms have been proposed in earlier research that can potentially lower the energy required by nearly 60 orders of magnitude.” -- Say…
If aliens ever visited us they may be blown away that the majority of our bodies are made up of rocket fuel.
Re: Breaking the warp barrier for faster-than-light travel
#26Earlier quoted context omitted.
I agree but the nearest star is (only?) 4 light years away. If we only managed to travel close to the speed of light, we surely live long enough today. Time dilation will cause our friends to be older by a few years than they should be, but not by that much right?
There is a cool calculator of what happen if you travel around with constant 1G acceleration. Long story short: to travel to Alpha Centauri it would take for the traveller still about 4 years, and when back at home, people would have aged only some months more than the astronauts. Crazy things happen if you decide to go on galaxy-wide trips though, to the astronauts because space contraction they perceive their own t…
I think you're forgetting that there's a hard upper limit on velocity.
Edit: Ah, wasn't aware of length contraction. https://courses.lumenlearning.com/physics/chapter/28-3-lengt...
Re: Breaking the warp barrier for faster-than-light travel
#27If warp drives actually are feasible (either sub or super liminal), that'd be great. However, it seems to me that it's much more likely we'll travel between stars as digitized minds that are recorporialized at the destination.
Re: Breaking the warp barrier for faster-than-light travel
#28It is early in the morning, so I'm still irritable, but this line is pretty egregious -- The energy savings would need to be drastic, of approximately 30 orders of magnitude to be in range of modern nuclear fission reactors.” He goes on to say: “Fortunately, several energy-saving mechanisms have been proposed in earlier research that can potentially lower the energy required by nearly 60 orders of magnitude.” -- Say…
It is a strangely worded sentence for sure, but it's probably referring to previous sensitivity analysis done on the original Alcubierre negative mass-energy requirements:
https://en.wikipedia.org/wiki/Alcubierre_drive#Difficulties
60 orders of magnitude is about the difference of the mass of the observable universe to 'a few milligrams'.
Re: Breaking the warp barrier for faster-than-light travel
#29Earlier quoted context omitted.
It currently requires 1e42 (say), and 30 orders of magnitude less brings it into the realm of possibility with a large power plant.
Continuing with the assumptions, it takes /us/ 1E42 watts, but the authors speculate that the universal lower bound is indistinguishable from 0. Much like how we can't make a useful fusion reactor, the universe at large has made loads of them because. If their suspicions are right and the lower bound is so low, it would need to be some incredibly contrived collection of events to not occur naturally with some regular…
An improbable drive?
Re: Breaking the warp barrier for faster-than-light travel
#30Earlier quoted context omitted.
There is a cool calculator of what happen if you travel around with constant 1G acceleration. Long story short: to travel to Alpha Centauri it would take for the traveller still about 4 years, and when back at home, people would have aged only some months more than the astronauts. Crazy things happen if you decide to go on galaxy-wide trips though, to the astronauts because space contraction they perceive their own t…
I think you're forgetting that there's a hard upper limit on velocity. Edit: Ah, wasn't aware of length contraction. https://courses.lumenlearning.com/physics/chapter/28-3-lengt...
Not on subjective velocity. As you approach the speed of light from an outsider's perspective from the insider's perspective the universe appears to shrink.