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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

#91

Post by jchrisa »

quickthrower2 wrote: post #58
jchrisa wrote: post #51

Earlier quoted context omitted.

> 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!

I imagine if there is any amount of angular momentum imparted to the water in our cells, the reversal of the force propelling it would create a turbulent episode of transition.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#92

Post by godelski »

evilduck wrote: post #89
godelski wrote: post #70

Earlier quoted context omitted.

This would also be neat. And of course any information communication. While Ansibles[0] are typically used to verbally communicate with someone why not any information? [0] https://en.wikipedia.org/wiki/Ansible

That was sort of a primary plot point of the Ender's Game series.

I wouldn't say primary plot of Ender's Game. I'd say it was a higher focus in Speaker for the Dead. Still, the device is used in a lot of Sci-Fis. Card wasn't even the first to use the term Ansible, though he did use that exact word.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#93

Post by godelski »

R0b0t1 wrote: post #73
godelski wrote: post #68

Earlier quoted context omitted.

> The macro evidence in that if FTL were possible it makes it that much more unlikely that we haven't detected starfaring life. I don't think this is a great argument. Even with FTL the galaxy (not universe) is huge. Let's just say you can go 2x (warp factor 1.25) it would still take more than 2 years to reach Alpha Centauri (our closest star, 4.37 lyr). Even at 8c (Warp 2) it would still take >6 months. At 100c it i…

I don't think it's fair to say "or immortality, or generational ships." You can make a one way trip, sometimes, but you can't meaningfully communicate. FTL is necessary or the universe is kind of boring on a grand scale.

What I'm saying is that you're not going to travel a meaningful distance in the Milky Way (as in percentage) within several lifetimes. Longer life or generational ships are absolutely necessary, even at high speeds and time dilation.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#94

Post by ehvatum »

mikewarot wrote: post #31
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…

We're all traveling through spacetime at the speed of light, most of our velocity is in the time dimension, the faster you translate in the x,y,z dimensions, the less is left over for the time dimension, and thus time seems to slow down. (That's how this non-physicist things about it, anyway) In a warp field, you're just somehow shrinking X,Y,Z while not doing the same to time. I see no reason to think you'd travel b…

Your thinking assumes a preferred reference frame. https://en.m.wikipedia.org/wiki/Relativity_of_simultaneity

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#95

Post by Bud »

postalrat wrote: post #72
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.

Occam's razor actually says that?

Yes. This is actually about as clear of an example as you can find of what it says.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#96

Post by a1369209993 »

javajosh wrote: post #88
a1369209993 wrote: post #77

Earlier quoted context omitted.

No, the meter is defined (as c times a certain number of seconds).

No, the meter is defined in terms of c and the hyperfine transition frequency of Cs-133 is defined https://physics.nist.gov/cgi-bin/cuu/Value?nucs . If that link isn't good enough, you can check out the SI Mises en pratique on the subject: https://www.bipm.org/en/publications/mises-en-pratique Edit: I'm totally this guy right now https://xkcd.com/386/

> the meter is defined in terms of c

That is what I just said: the meter is defined in terms of c, not vice versa.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#97

Post by R0b0t1 »

hallway_monitor wrote: post #86
R0b0t1 wrote: post #73

Earlier quoted context omitted.

I don't think it's fair to say "or immortality, or generational ships." You can make a one way trip, sometimes, but you can't meaningfully communicate. FTL is necessary or the universe is kind of boring on a grand scale.

It's not boring, it's just too big and therefore too slow for our tastes. If we lived 5,000 years, taking a 100 year trip to Alpha Centauri might not seem so bad. I think extending lifespan like this is more likely than building an FTL drive.

My concern is the mismatch between the timescale we communicate with people and the timescale of the trips (minutes or hours vs centuries). It would be such a massive transition during your trip that it is hard to adequately describe it.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#98

Post by lamontcg »

incompatible wrote: post #17
TheDudeMan wrote: post #16

Earlier quoted context omitted.

"effectively traveling into your own past" Can you explain how traveling faster than light leads to that? Perhaps you meant "observing your own past?"

I'd guess there would be frames of reference (with relative high-speed motion) in which you'd appear at the destination before you've left the origin. The laws of physics are supposed to hold regardless of which frame of reference you use.

You could break the problem of closed timelike loops by having a preferred reference frame for the Universe where nothing could travel backwards in time relative to that reference frame. And the CMBR rest frame might be an artifact of that preferred reference frame existing in the early Universe.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#99

Post by tsimionescu »

XorNot wrote: post #11
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…

Well for one thing, a speed-of-light limited warp drive would still be effectively a reaction-less drive we could use for travel in the solar system. But a decent way to beat Einstein would be find and implement an actual FTL engine: after all, if you can do it then obviously the theory isn't correct (alternately: the universe possible does not care about causality as much as we do in our little bubble of perception)…

The whole point of warp drive FTL, and the reason it's the only kind of FTL idea taken seriously, is that it wouldn't violate GR. We already have widely accepted physical theories that contain exactly this kind of FTL 'travel': the Big Bang theory posits that space in the early universe expanded faster than the speed of light.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#100

Post by akiselev »

samplatt wrote: post #44
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…

>It'd be able to enter warp once. ...why once? Are you assuming all matter+antimatter is destroyed in the single trip? If you have x amount of critical material, could you not warp for half the distance of the "fuel" in your "tank" and then come back? IANAPhyicist. I'm assuming that if we have the ability to contain and harvest energy from a matter/antimatter reaction then we also have the ability to stop it & start…

The way I said it is misleading for the sake of brevity. That's a small gas giant worth of matter and antimatter to power a warp drive for a ship so small that it's not even worth calculating its mass relative to the fuel. The entire mass of Mount Everest is something like 0.00000000001% of the mass you'd need to create the warp bubble. If the ship was in the center of the fuel, it'd be crushed into something so dense it'd resemble the earth's core.

Best case scenario we're talking a mass effect style planetary megastructure that forms a warp bubble around a ship and shoots it with just enough "momentum" for the warp bubble to fail right at the destination.

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