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Positive Energy Warp Drive from Hidden Geometric Structures

arxiv.org

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Re: Positive Energy Warp Drive from Hidden Geometric Structures

#51

Post by jchrisa »

nine_k wrote: post #41
gary_0 wrote: post #30

Earlier quoted context omitted.

"Turning around" is just stopping at some point (ie. some inertial reference frame) and then accelerating in the opposite direction with your FTL drive. You have all the time in the world to do this maneuver because you're already effectively in the past: https://physics.stackexchange.com/a/54242

There's no absolute coordinate system in space, so there's no way to "stop". You can only change your velocity relative to some other object, e.g. your past self in the example. What counts is acceleration / deceleration. Slowing down to reach the speed of light might be as hard as speeding up to reach it; I remember it played a role in the theory of tachyons, hypothetical FTL elementary particles which could not be…

> acceleration / deceleration

Another question for the thread: Anyone here feel like they can feel the Coriolis effect if they focus enough? I haven't travelled across the equator enough to know if the north/south jetlag is different from east/west.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#52

Post by AnimalMuppet »

TrevorJ wrote: post #21
akiselev wrote: post #5

Earlier quoted context omitted.

The first paper detailing the Alcubierre drive required exotic particles with negative mass to achieve a spacetime bubble (soliton) which is an issue since particles with negative mass have never been observed. The next big paper figured out how to do it with regular matter and it brought the requirements down to the energy equivalent of four solar masses. That would put it squarely into the realm of a type II or III…

Would be interesting if paired with the harvesting of energy from a black hole. It is theorized that you can do this 'remotely' by slingshotting a laser around a black hole. This functions the same way a normal gravity assist does, except in this case it's photons, and not spacecraft. Shoot a laser around one side of a black hole, it returns to you around the other side, but at a higher energy wavelength. In this way…

If your laser beam doesn't spread so far that you can't harvest enough energy to be net positive, then the black hole is not going to be a safe distance away.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#53

Post by randmeerkat »

IdiocyInAction wrote: post #47
jack_pp wrote: post #43

Earlier quoted context omitted.

Isn't there evidence starting to surface that we have actually detected alien contact?

You mean that UAP stuff? Occam's razor says this is probably some electronic countermeasure stuff by the US or something.

Maybe, or what if it’s exactly what the DoD is saying? That there’s verified advanced UAPs beyond our current technological understanding.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#54

Post by stjohnswarts »

randmeerkat wrote: post #53
IdiocyInAction wrote: post #47

Earlier quoted context omitted.

You mean that UAP stuff? Occam's razor says this is probably some electronic countermeasure stuff by the US or something.

Maybe, or what if it’s exactly what the DoD is saying? That there’s verified advanced UAPs beyond our current technological understanding.

I don't they said "there are uaps beyond..." , they said they couldn't explain all of them, that's all.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#55

Post by stjohnswarts »

gary_0 wrote: post #9

What do the authors of these warp drive papers think will happen causality-wise when the proposed vehicle effectively moves faster than c? You can't do that without doing nasty things to your light cone[0] and effectively traveling into your own past. Is a prerequisite of entertaining the idea of a warp drive that we disregard causality? As far as I know, there aren't any plausible loopholes in General Relativity tha…

These drives don't violate causation, they warp space. Similar to the way expansion of the early universe could "move faster than the speed of light"

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#56

Post by mmazing »

cletus wrote: post #39

The lesson we should really take here is the power of wishful thinking. People dearly want to believe in FTL travel. Without it, the Universe just seems so vast, empty and distant. The truth is it is and it isn't. It's only really that on our current time scales. Not to be a broken record (there's some new variation on some old idea like every week it seems), but I'm firmly in the camp that believes FTL isn't possibl…

Wouldn't space-faring civilizations be more likely to exist along the galactic plane, which we have a much harder time examining?

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#57

Post by api »

If FTL is possible (and engineerable) then the Fermi paradox becomes a serious problem. There "should" be aliens all over the place unless...

(1) We are wrong about the nature of the universe and strong theism / creationism or the simulation hypothesis (which is the same thing more or less) are right.

(2) Life or complex life are so phenomenally unlikely that we are literally the only example in the local galactic supercluster at least, if not the whole universe. Speaking of creationists they often argue that the probability of life forming from non-life is insanely low. Maybe they're right about those probabilities and it only happened once.

(3) We live in a cosmic cemetery. There is a big nasty great filter ahead of us, and nobody has passed so far. Maybe the great filter is when you try to actually build FTL and cause a space-time catastrophe.

(4) We live in a "dark forest" and should be very, very quiet. Shhhhh....

(5) We live in a nature preserve. See #6.

(6) Last but not least, at least some UFOs really are ETs in which case there is no Fermi paradox. They're here and we have seen them. They're just laying low and not making overt contact.

My money would be on 6. If we demonstrated some kind of engineerable FTL I'd take the possibility that at least a few UFOs are ETs very seriously.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#58

Post by quickthrower2 »

jchrisa wrote: post #51
nine_k wrote: post #41

Earlier quoted context omitted.

There's no absolute coordinate system in space, so there's no way to "stop". You can only change your velocity relative to some other object, e.g. your past self in the example. What counts is acceleration / deceleration. Slowing down to reach the speed of light might be as hard as speeding up to reach it; I remember it played a role in the theory of tachyons, hypothetical FTL elementary particles which could not be…

> acceleration / deceleration Another question for the thread: Anyone here feel like they can feel the Coriolis effect if they focus enough? I haven't travelled across the equator enough to know if the north/south jetlag is different from east/west.

How would you feel the effect? If you do it's more likely to be placebo as you can't avoid knowing where in the world you are!

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#59

Post by [deleted] »

gary_0 wrote: post #9

What do the authors of these warp drive papers think will happen causality-wise when the proposed vehicle effectively moves faster than c? You can't do that without doing nasty things to your light cone[0] and effectively traveling into your own past. Is a prerequisite of entertaining the idea of a warp drive that we disregard causality? As far as I know, there aren't any plausible loopholes in General Relativity tha…

[deleted]

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#60

Post by api »

stjohnswarts wrote: post #55
gary_0 wrote: post #9

What do the authors of these warp drive papers think will happen causality-wise when the proposed vehicle effectively moves faster than c? You can't do that without doing nasty things to your light cone[0] and effectively traveling into your own past. Is a prerequisite of entertaining the idea of a warp drive that we disregard causality? As far as I know, there aren't any plausible loopholes in General Relativity tha…

These drives don't violate causation, they warp space. Similar to the way expansion of the early universe could "move faster than the speed of light"

What happens if you're between the drive and the destination? Do you experience spatial contraction too?

If not then the spacecraft is traveling faster than 'c' with regard to everything not in its reference frame (right?). If this kind of thing is possible then the universe is considerably weirder than we thought even after a hundred years or so of QM.

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