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Breaking the warp barrier for faster-than-light travel

uni-goettingen.de

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Re: Breaking the warp barrier for faster-than-light travel

#51

Post by simiones »

SketchySeaBeast wrote: post #38
speeder wrote: post #34

Earlier quoted context omitted.

You never reach that limit if you are accelerating with a normal engine at 1g. You will get closer and closer to it, but never reach it. If you somehow DO achieve lightspeed, time stops for you, completely, so from your point of view you are teleporting, but since time is stopped no machine or chemical reaction can happen, thus why we believe lightspeed machinery is impossible. By the way, achieving near lightspeed w…

> 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 your frame of reference, the universe is much smaller in the direction of travel. You'd still see light zoom past you at 1c, though.

Re: Breaking the warp barrier for faster-than-light travel

#52

Post by zaarn »

SketchySeaBeast wrote: post #38
speeder wrote: post #34

Earlier quoted context omitted.

You never reach that limit if you are accelerating with a normal engine at 1g. You will get closer and closer to it, but never reach it. If you somehow DO achieve lightspeed, time stops for you, completely, so from your point of view you are teleporting, but since time is stopped no machine or chemical reaction can happen, thus why we believe lightspeed machinery is impossible. By the way, achieving near lightspeed w…

> 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 your perspective, the entire length of the milky way is squished into 22 light years (roughly), so not really violating anything. From the outside frame of reference you still take 10000 years (plus) to cross that distance, from your perspective, the distance gets shorter.

Re: Breaking the warp barrier for faster-than-light travel

#53

Post by zaarn »

komon wrote: post #42
nynx wrote: post #27

If 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.

That's only going to become a solution if you can convince people that the process preserves continuity of experience. How do I know that I actually wake up on the other side, instead of dying and having a clone with my memories wake up instead?

The video game SOMA deals with these issues to some extend; Who is the real you if you copy-paste yourself over to a new body? And what about the you that stayed behind?

Re: Breaking the warp barrier for faster-than-light travel

#54

Post by simiones »

SketchySeaBeast wrote: post #48
akvadrako wrote: post #46

Earlier quoted context omitted.

From your own perspective you are always stationary, it's just the universe that is moving (and shrinking).

Quote from the original claim: > 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. They are saying add a constant 1g acceleration and you can get anywhere relatively quickly, no…

No, you're misunderstanding.

From your frame of reference, the universe is much flatter in the direction of travel, and getting flatter and flatter the more time you spend. The distance between Earth and the edge of the galaxy will get smaller and smaller in your direction of travel.

Re: Breaking the warp barrier for faster-than-light travel

#55

Post by maxerickson »

SketchySeaBeast wrote: post #48
akvadrako wrote: post #46

Earlier quoted context omitted.

From your own perspective you are always stationary, it's just the universe that is moving (and shrinking).

Quote from the original claim: > 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. They are saying add a constant 1g acceleration and you can get anywhere relatively quickly, no…

When you go fast, subjective experience slows down.

You'd have 22 years of thoughts, for example, even though 10,000 years of stuff happened elsewhere.

From the perspective of an observer on earth, the trip takes a long time. The people on the spaceship experience 22 years.

Re: Breaking the warp barrier for faster-than-light travel

#56

Post by mooseburger »

nynx wrote: post #45
komon wrote: post #42

Earlier quoted context omitted.

That's only going to become a solution if you can convince people that the process preserves continuity of experience. How do I know that I actually wake up on the other side, instead of dying and having a clone with my memories wake up instead?

I don't really see a difference. You experience a discontinuity every night when you sleep. Of course, this entire concept is reliant on materialism. If you believe in a soul, then I'd probably find it difficult to convince you that a digital copy of you is close enough to being you.

> you experience discontinuity every night when you sleep

Something dubious about this. No one thinks they're annhiliated upon sleeping, then reconstituted upon waking.

Even adhering to materialism, the problem with mind uploads is the same problem as with teleportation: a copy is being made. Destroying the original does not mean a consciousness transfer then magically occurs from the original to the target. For mind uploads, the only plausible sounding way around this is the Moravec transfer, but even that is reliant on the Ship of Theseus thought experiment having a definite answer.

Re: Breaking the warp barrier for faster-than-light travel

#57

Post by nynx »

mooseburger wrote: post #56
nynx wrote: post #45

Earlier quoted context omitted.

I don't really see a difference. You experience a discontinuity every night when you sleep. Of course, this entire concept is reliant on materialism. If you believe in a soul, then I'd probably find it difficult to convince you that a digital copy of you is close enough to being you.

> you experience discontinuity every night when you sleep Something dubious about this. No one thinks they're annhiliated upon sleeping, then reconstituted upon waking. Even adhering to materialism, the problem with mind uploads is the same problem as with teleportation: a copy is being made. Destroying the original does not mean a consciousness transfer then magically occurs from the original to the target. For mind…

Some people do think that. There are whole fields of philosophy about it.

> Even adhering to materialism, the problem...

If you don’t require continuous experience, then this issue goes away. You certainly didn’t experience living before you were conceived. My view is that consciousness is an emergent property of informational and processing structure of the brain (and possible other systems as well)—-I don’t see any physical issues with copies (other than that it might result in confusion and social problems).

Re: Breaking the warp barrier for faster-than-light travel

#58

Post by Delk »

captainmuon wrote: post #41
wolfram74 wrote: post #10

It 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…

University of Göttingen alum here, in our astrophysics courses we used to make jokes about how generous the approximations were. Comparing x^2 with x^5, take log on both sides, 2 ~= 5, so x^2 = x^5 ... Appropriate xkcd: https://xkcd.com/2205/

Something makes me want to continue that xkcd strip with a CS approximation with something about all of those being just constant factors.

Re: Breaking the warp barrier for faster-than-light travel

#59

Post by drchickensalad »

SketchySeaBeast wrote: post #48
akvadrako wrote: post #46

Earlier quoted context omitted.

From your own perspective you are always stationary, it's just the universe that is moving (and shrinking).

Quote from the original claim: > 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. They are saying add a constant 1g acceleration and you can get anywhere relatively quickly, no…

You move at a constant vector, the speed of light, through both space and time. Since you go from basically 0 magnitude in space (anything us humans do on earth) to approaching the speed of light, that robs direction from the time magnitude. Therefore, going that quickly means you experience substantially less time. Taken to the extreme, when you move at the speed of light, you experience no time; you would simply from a human perspective teleport to the place where you start decelerating (given that's possible lol).

Re: Breaking the warp barrier for faster-than-light travel

#60

Post by sudosysgen »

rrmm wrote: post #36
IHLayman wrote: post #23

I 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?

It usually requires exotic matter with negative mass which isn't normally found.

This one supposedly doesn't, which is why it's so newsworthy.
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