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General Discussion => New Physics for Space Technology => Topic started by: TomH on 06/12/2014 01:46 am

Title: No Joke: NASA Working on Warp Drive
Post by: TomH on 06/12/2014 01:46 am
And they have named the first model Enterprise. Supposedly, the unimaginable amount of energy first thought required for warp drive has been reduced greatly. NASA actually has people working on generating warp fields.

http://www.washingtonpost.com/news/post-nation/wp/2014/06/11/this-is-the-amazing-design-for-nasas-star-trek-style-space-ship-the-ixs-enterprise/
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Cinder on 06/12/2014 01:57 am
Search for "Sonny White" in this Advanced Concepts forum and you'll find previous coverage.   

Quantum vacuum plasma thruster (Q-thruster)  Late 2013 topic
http://forum.nasaspaceflight.com/index.php?topic=33220.0

New hope for Warp Drive concept? - Late 2012 topic. 
http://forum.nasaspaceflight.com/index.php?topic=29924.0

Dr. Harold (Sonny) White.   Early 2011 topic
http://forum.nasaspaceflight.com/index.php?topic=24325.0 


Propellantless Field Propulsion and application - older general topic incl. Mach Effect and others, with many comments by Paul March who IIRC now works at Eagleworks with White.
http://forum.nasaspaceflight.com/index.php?topic=13020.0
Title: Re: No Joke: NASA Working on Warp Drive
Post by: TomH on 06/12/2014 02:10 am
Thanks for those threads. Apparently what's new is proof of concept experiments.

I remember when the theory was announced 20 years ago one physicist said a few seconds of warp drive would require as much energy as Sol (our star) will put out during its entire approx. 10 billion year lifetime. I then remember a couple of minor statements in the general press a couple of years ago that there may be a way to reduce the energy requirement.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: aceshigh on 06/12/2014 02:12 am
NASA didn´t name the ship anything, nor are they really working on a "warp drive".

these renders were comissioned by Dr White himself, and since this guy used to do other spaceship renders, apparently several related to Star Trek, I think he himself named the ship as Enterprise. The ship is just an artistic impression of how a warp drive ship would look like according to Dr White.

Also, "working a warp drive" is a bit far fetched. Eagleworks is investigating IF a warp drive is possible with ZDF theory, which Dr White believes it is. So the only thing being done as far as I know is testings of spacetime nano-deformations using a laser interferometer, but there is talk the results have been negative...
Title: Re: No Joke: NASA Working on Warp Drive
Post by: aceshigh on 06/12/2014 02:17 am
Thanks for those threads. Apparently what's new is proof of concept experiments.

eh? What do you mean with "proof of concept"? I don´t think they went farther yet then verifying if they can do nano deformations at spacetime.


Quote
I remember when the theory was announced 20 years ago one physicist said a few seconds of warp drive would require as much energy as Sol (our star) will put out during its entire approx. 10 billion year lifetime. I then remember a couple of minor statements in the general press a couple of years ago that there may be a way to reduce the energy requirement.

that´s the crux of Dr White's work on Warp. We have two distinct things here to consider:
1 - Dr White calculations on how to reduce the negative/exotic mass requirements from a Sun/Jupiter, to a single ton of exotic mass, by changing the rings width, oscilating the fields, etc, thus "softening" spacetime structure

2 - how to GET negative mass in the first place, which as far as I understand is what he is trying to do, through ZPF (Zero Point Field), then measuring it with the laser interferometer.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: GalacticIntruder on 06/12/2014 02:31 am
Well, we won't be creating and manipulating 'negative' energy in a usable way for a very, very, very long time. No FTL. But the Q thrusters could advance spaceflight substantially in our lifetimes.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: NovaSilisko on 06/12/2014 05:00 am
This keeps happening! One man from NASA comissioning an artist to make a spaceship doesn't make it a NASA project arargahrhghrgh

It gets problematic because I've noticed in the past that some folk end up saying things like "I thought NASA was working on a warp drive! Why are they doing all this other stuff?"
Title: No Joke: NASA Working on Warp Drive
Post by: Star One on 06/12/2014 07:24 am
I believe this is the original article for the story.

http://sploid.gizmodo.com/holy-crap-nasas-interplanetary-spaceship-concept-is-fr-1589001939/1589277571/+jesusdiaz
Title: Re: No Joke: NASA Working on Warp Drive
Post by: RanulfC on 06/12/2014 12:28 pm
This keeps happening! One man from NASA comissioning an artist to make a spaceship doesn't make it a NASA project arargahrhghrgh

It gets problematic because I've noticed in the past that some folk end up saying things like "I thought NASA was working on a warp drive! Why are they doing all this other stuff?"

Neat looking ship though :)

Randy
Title: Re: No Joke: NASA Working on Warp Drive
Post by: JohnFornaro on 06/12/2014 01:55 pm
This keeps happening! One man from NASA comissioning an artist to make a spaceship doesn't make it a NASA project arargahrhghrgh

It gets problematic because I've noticed in the past that some folk end up saying things like "I thought NASA was working on a warp drive! Why are they doing all this other stuff?"

I call bogosity on the scientainment.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: DMeader on 06/12/2014 05:29 pm
Yes, joke.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/12/2014 10:12 pm
just a few observations:

The results were not negative as of the last briefing that exists  in the video world. Dr White says he got some results suggestive of deformation but that the results were not robust enough to meet standards of proof for an extraordinary claim *YET.* Also he said that a colleague convinced him that a different type of interferometry instrument would be much better. He was unfamiliar with the operation and set up of said interferometer so his colleague was instructing him on it's proper set up and use. he said that he would be running further trials with the new set up. He also said he was going to construct a stronger test article instead of using the repurposed QVPT thing he had pressed into service for his first set of experiments.

He also said that he thinks it may be possible to forego negative energy requirements with the right design.

The current energy requirements are based upon assumptions and parameters which Dr White says he has not optimized. he only worked on that until he had values that would move the concept from impossible to possible. by tweaking the design and parameters further he thinks the energy requirements can be driven down further.

the current estimate is still staggeringly large and beyond our capability of producing. it is the same amount of energy that would be liberated by converting the entire mass of the voyager space probe to energy. that is many times more power than than all the atomic bombs ever made on earth by everybody who ever made them on earth from the beginning of the atomic age going off at once.

just because Dr white was not satisfied with the sigma level of his data and analysis does not mean he reported negative results. he said quite the opposite. (that the preliminary results were suggestive that he had detected a warp and he was encouraged by them) that is... unless there was a report after the one i saw.

and finally; this new article which saw as well has no update on anything we didn't already know. when i saw it i hoped for an update on his test data or at least an announcement of the resumption of his test runs or completion of the new lab set up and test articles and equipment. The Model is simply a better rendering of something he had already shown in his briefings. in short it appears to be a bit fluffy as articles go.

EDIT:  this is the latest thing i have seen that involved Dr White briefing on his experiments. is there something newer that contains new information i have missed?

https://www.youtube.com/watch?v=aLc-sKvFqJw
Title: Re: No Joke: NASA Working on Warp Drive
Post by: drbuzz0 on 06/13/2014 10:24 pm
I did some calculations and was surprised to find that the amount of energy needed is decidedly not impossible.  They sometimes quote the amount of energy needed by the redesigns as being about the mass of a Voyager probe.   That's a lot of energy, actually, if you are talking mass-energy equivalence (which they are).  It's basically saying you would have several hundred kilograms of matter and antimatter reacting.

It turns out that the amount of energy they are talking about, in the optimistic, efficient schemes that use a ringed spacecraft is something on the order of 50-75 exajoules.  (give or take) to get to a local star by warping space.  That's a mass energy equivalent of several hundred kilograms.

That's a difficult amount of energy, but, not actually an impossible amount.

If you figure the most energetic thing humanity ever put into a small package is the AN602 hydrogen bomb - known as the "Tsar Bomba"  It had a full design yield of 100 megatons.  (It was tested at less than this by replacing the uranium tamper with an inert one of tungsten)   That is 410 petajoules.  or .41 extajoules.  So what we would need is the energy equivalent of hundreds of very high yield h-bombs.

I have no idea how that energy would be contained and channeled into warping space, as opposed to just blowing things up, but it's an amount of energy that current technology could deliver.   

Hundreds of big h-bombs would be expensive.  They'd be heavy and take a lot of rockets to just get out of the atmosphere.  And again, I have no idea how that raw explosive energy could be used for this.  BUT, it is humanly possible to get that much energy.

Title: Re: No Joke: NASA Working on Warp Drive
Post by: drbuzz0 on 06/13/2014 10:30 pm
A quick follow-up.  If you want to express that energy in terms of high yield nuclear explosives (again, those being the most energetic things we can produce), a better example is the US B41 bomb.  It was 25 megatons, so it was only 1/4 as powerful as the Tsar Bomba.  But it is far more efficient.  It has a much better ratio of yield to mass.  Also, the AN602 was not produced in mass.  One test device was made and possibly a few others, but not a huge number.

http://en.wikipedia.org/wiki/B41_nuclear_bomb

The B41 was mass produced to a quantity of about 500 (although not all versions were the 25 megaton high yield variation)

You would need 700 of these things to produce enough energy.  So, again, not an impossible number.

The mass is ten metric tons each.  So you'd need a large, but not impossibly large number of rockets to get them into space, where presumably, you would start your warp drive from.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: savuporo on 06/13/2014 10:52 pm
You would need 700 of these things to produce enough energy.  So, again, not an impossible number.

The mass is ten metric tons each.  So you'd need a large, but not impossibly large number of rockets to get them into space, where presumably, you would start your warp drive from.

If you do, please do it on the other side of Jupiter just in case. Thanks.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: hop on 06/14/2014 02:59 am
FWIW, Miguel Alcubierre commented https://twitter.com/malcubierre/status/477422940628078592
Quote
Before you ask me about this supposed design for a starship, please read this! http://excursionset.com/blog/2014/6/13/lets-do-the-space-warp-again

And read also this: http://www.slate.com/articles/health_and_science/science/2013/08/harold_sonny_white_warp_drive_faster_than_light_secret_physics_debunked.html
Title: Re: No Joke: NASA Working on Warp Drive
Post by: KelvinZero on 06/14/2014 04:18 am
With any FTL proposal, I always wish there were an attempt to explore the most critical question of the apparent paradoxes. Otherwise you essentially have this:

https://www.youtube.com/watch?v=TkZFuKHXa7w
Title: Re: No Joke: NASA Working on Warp Drive
Post by: cordwainer on 06/14/2014 05:49 am
I think we should reserve judgement regarding Sonny White's progress in this field. His math is pretty solid and he hasn't claimed in any way shape or form that he is capable of creating negative energy or exotic matter.

Instead he is claiming that he may have developed diagnostic tools for detecting negative energy and quantum fluctuations which in turn could be used to discover exotic matter of zero-point energy manifestations.

His modifications to Alcubierre's warp bubble physics have been peer reviewed and in theory could work if we could produce negative energy and the sizable positive energy requirement needed. Personally, I think that it would be highly unlikely we could ever get the sizable amount of positive or negative energy needed from ZPF, but if ZPF can be detected and manipulated or exploited in some way the ramifications could be immense.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: MATTBLAK on 06/14/2014 06:56 am
Warp Drive; developed or funded within the lifetimes of anyone reading this?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: john smith 19 on 06/14/2014 09:23 am
just a few observations:

The results were not negative as of the last briefing that exists  in the video world. Dr White says he got some results suggestive of deformation but that the results were not robust enough to meet standards of proof for an extraordinary claim *YET.* Also he said that a colleague convinced him that a different type of interferometry instrument would be much better. He was unfamiliar with the operation and set up of said interferometer so his colleague was instructing him on it's proper set up and use. he said that he would be running further trials with the new set up. He also said he was going to construct a stronger test article instead of using the repurposed QVPT thing he had pressed into service for his first set of experiments.
Watching the video (it glitched for me about 26:00 for a minute or two) you actually note how very cautious he is about the results. It's also clear that their work is being tried at other sites and multiple different approaches (with different hardware) to ensure it's not a measurement artifact.

I'll also note that the "Q Thruster" work they are doing is not the wormhole work and seems to have yielded some practical results. He talked about 0.1N/Kw of power. Mission concepts for a 70 tonne spacecraft (50 tonne payload 20tonnes for the 2MW nuclear drive and a lot of individual Q thrusters) Jupiter in <1 year, Pluto in < 5yr  :o (reactor power density at 10 Kg/Kw is within SoA) the other implication being station keeping propellant depletion is no longer a life ending mode for comm sats.

Listening to his presentation I wonder if he's ever read "Instruments and experiences" by Dr RV Jones. Jones work involved a lot of optical lever work and "kinematic" motion using flexure joints and levers to deliver nm displacements in a conventional lab environment in the 1950's. White's comments echoed Jones work on seismometers on sensitivity (It's an excellent book. Part memoir, part collection of scientific papers  :) )

I cannot say if all the positive results are measurement artifacts and Dr White is deluding himself that this can work. What I can say is that this work has taken a concept that needed to turn a mass equal to Jupiter into energy and reduced by about 24 orders of magnitude suggests there is scope for more improvement. IIRC this programme costs $1/2m a year, roughly 1/3000 of SLS (mind you if he'd had to build that vibration isolated lab from scratch that would have added a few noughts  :) ). It's an extraordinary plan and will need extraordinary proof to convince most people but for that kind of money that seems like a worthwhile trade off.

I think "You can go to Jupiter in less than 1 year (with a Q thruster away, no FTL needed)" is a hell of a positive message. Developing a large space rated reactor is challenging but AFAIK this is the only source that could deliver the power you'd need if you wanted to build even an uncrewed star probe. White's reference design is 10m in size. Reusing the power unit from a Jupiter ship you could probably send small instrument packages to anywhere in a 170 LY radius of Earth with the same sort of delay in results as Voyager took in delivering it's outer planet results.

That's a huge amount of space (and stars) to explore at 10C.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/14/2014 10:38 am
I've not been following the Q-thruster stuff too closely - is there a plausible story yet about how it doesn't violate conservation of energy? (a question that any purported reactionless drive needs to be able to answer)

does it abide by the photon rocket limit?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: ChrisWilson68 on 06/14/2014 11:11 am
just because Dr white was not satisfied with the sigma level of his data and analysis does not mean he reported negative results. he said quite the opposite. (that the preliminary results were suggestive that he had detected a warp and he was encouraged by them) that is... unless there was a report after the one i saw.

"Not satisfied with the sigma level" means statistical analysis of the data did not support the conclusion.  That's a negative result.  At least it's a negative result to real scientists.  White not reporting it doesn't mean the result wasn't negative.  A preliminary result is what you get when you are doing a preliminary test, not when you do a rigorous experiment and it doesn't give the results you like.

(Also, why is it that some parts of your post follow standard capitalization rules and some do not?  Do you not realize that standard capitalization lets people read more quickly?  By putting a little more effort into generating your content, you will be aiding the many people you are asking to read it by posting.)
Title: Re: No Joke: NASA Working on Warp Drive
Post by: SteveKelsey on 06/14/2014 11:24 am
No it doesn't mean a negative result, even to real scientists. It means he had a result but it's not clear enough to be decisive. It means more work needs to be done. Inconclusive yes, negative, no. This is difficult work and casual refutations are to easy.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: ChrisWilson68 on 06/14/2014 11:38 am
No it doesn't mean a negative result, even to real scientists. It means he had a result but it's not clear enough to be decisive. It means more work needs to be done. Inconclusive yes, negative, no. This is difficult work and casual refutations are to easy.

No, it's you who is wrong.

Not meeting the bar of statistical significance is a negative result for an experiment.

You're confusing a negative result with proof that the hypothesis is false.  That's not what "negative result" means in science.  It means the experiment failed to provide sufficient evidence of the hypothesis.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: SteveKelsey on 06/14/2014 12:16 pm
http://rationalwiki.org/wiki/Statistical_significance

You may find the section on 'The problems with statistical significance' interesting reading
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/14/2014 02:21 pm





White's reference design is 10m in size. Reusing the power unit from a Jupiter ship you could probably send small instrument packages to anywhere in a 170 LY radius of Earth with the same sort of delay in results as Voyager took in delivering it's outer planet results.

That's a huge amount of space (and stars) to explore at 10C.

Well i won't speak to the negative energy that white needs and is given off amply by stuffed shirt skeptics for the moment.  ;)

But other than that i have more good news for you. That 10C upper limit thing. Isn't. That figure was arrived at by using a series of assumptions. one assumption he used was that the craft could get to 10 percent C in regular space by using a thruster of some sort.

the rest of the assumptions had to do with what the warp drive could do with that speed once it was turned on. there were several factors involved in that but long story short:

if you could go faster than .10 c in real space his warp drive would multiply that by his warp factor as well. so .5 c would translate (without changing anything else) into 50 C or something like that.

on top of that the thing could be sped up by messing with his other parameters a bit just like he did to arrive and his energy consumption figures. He has stated that those are not fully optimized yet either so there is logic behind the idea those could be improved too.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/14/2014 03:06 pm
I've not been following the Q-thruster stuff too closely - is there a plausible story yet about how it doesn't violate conservation of energy? (a question that any purported reactionless drive needs to be able to answer)

does it abide by the photon rocket limit?
I too would like to know this...
There must be some mechanism that limits the Q-thruster/Woodward drive vehicle so that the energy supplied in accelerating it is always greater than
(http://upload.wikimedia.org/math/9/f/3/9f3d089c43d0ac712f710a8be8fd1aea.png)

Does anyone know what that mechanism is?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Burninate on 06/14/2014 03:48 pm
FWIW, Miguel Alcubierre commented https://twitter.com/malcubierre/status/477422940628078592
Quote
Before you ask me about this supposed design for a starship, please read this! http://excursionset.com/blog/2014/6/13/lets-do-the-space-warp-again

And read also this: http://www.slate.com/articles/health_and_science/science/2013/08/harold_sonny_white_warp_drive_faster_than_light_secret_physics_debunked.html
Conclusions:
Quote
However many hits this generates, NASA is squandering reputational credit on junk science and serious outlets are running this clickbait as news without applying even the most cursory of sniff-tests. I wish it wasn't true.
Quote
From what physicists have learned about the universe and its contents, White's warp drive can't work, period. If White has found a new method for generating negative energy, he hasn't published it, which means there's no way for other scientists to test his claims experimentally—or even check his calculations. Science requires its practitioners collectively to keep each other honest. For all the flaws in peer review and academic publishing, true suppression of ideas is rare. Until White publicizes the details of his research, our best option is to assume that what we know about quantum physics is correct—and his warp drive is still science fiction.

Thread should probably be locked. Alcubierre drives, and the artists paid to illustrate something that looks futuristic with no basis in fact and label it 'Alcubierre drive', amount to trolling at this point in the progression of physics & engineering.  Science fiction paints a more convincing picture most of the time.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/14/2014 03:51 pm
I've not been following the Q-thruster stuff too closely - is there a plausible story yet about how it doesn't violate conservation of energy? (a question that any purported reactionless drive needs to be able to answer)

does it abide by the photon rocket limit?
I too would like to know this...
There must be some mechanism that limits the Q-thruster/Woodward drive vehicle so that the energy supplied in accelerating it is always greater than
(http://upload.wikimedia.org/math/9/f/3/9f3d089c43d0ac712f710a8be8fd1aea.png)

Does anyone know what that mechanism is?

That's true as well I suppose, but not what I'm wondering about - if you have something that provides constant thrust for a given power, the integrated energy input is a linear function of time, but the kinetic energy gained is a quadratic function of time, and will inevitably overtake the energy input.

(photon rockets don't suffer from this, because according to a stationary observer the thrust decreases as the rocket gets faster due to redshift)
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/14/2014 03:55 pm
That's my point! What physical mechanism restricts the KE gained to satisfy conservation of energy...
IMHO there must be one, otherwise the Q-thruster/Woodward drives are fanciful. Which would be a great shame.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/14/2014 04:19 pm
i might add that even if there is no .1 C conventional drive his warp if successful would make for really short trip times at more realistic levels of conventional propulsion.

we might not get 10 c but having 100 times the transit speed of our current fastest probes would be wonderful. it would eliminate the radiation problem. it would greatly reduce the consumables and life support problems. it would mean more space and mass allowances for equipment and materials for use at the various destinations such a craft could get to right here in this solar system.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: john smith 19 on 06/14/2014 05:15 pm
i might add that even if there is no .1 C conventional drive his warp if successful would make for really short trip times at more realistic levels of conventional propulsion.

we might not get 10 c but having 100 times the transit speed of our current fastest probes would be wonderful. it would eliminate the radiation problem. it would greatly reduce the consumables and life support problems. it would mean more space and mass allowances for equipment and materials for use at the various destinations such a craft could get to right here in this solar system.
0.1C does not sound that tough but that's still a long way above what we've achieved so far.  :(
The BIS"Daedalus" project of the late 1970's reckoned 0.03C would be pretty tough, and they wanted to mine Jupiter's atmosphere for the fuel.

Which raises an interesting question. Are there any theoretical limits on the shortest jump you could take?

Assuming this can be made to work I'd want to test it in LEO (or the Moon) at the latest. Getting (say) half way to Jupiter and have a drive failure would not be a good idea.  :(

A system doing short jumps could accelerate between them in space, every m/s gained being multiplied by the warp drive.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Robotbeat on 06/14/2014 05:29 pm
Oh, it's the same old capacitors/reactionless shtick. Next thread!
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/14/2014 05:49 pm
Oh, it's the same old capacitors/reactionless shtick. Next thread!
Granted. It wont work if my inequality above us violated, but why not in general. Can you prove such a thing is impossible?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Nomadd on 06/14/2014 05:57 pm
Oh, it's the same old capacitors/reactionless shtick. Next thread!
Granted. It wont work if my inequality above us violated, but why not in general. Can you prove such a thing is impossible?
No, but he can prove that anyone who claims validity because you can't "prove it's impossible" has little chance of being taken seriously by anyone who didn't sleep through Physics 101.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/14/2014 06:02 pm
You miss my point. Q-thruster/woodward drive is physically possible if the above inequality is true.
Disprove this if you can...
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Robotbeat on 06/14/2014 06:07 pm
You miss my point. Q-thruster/woodward drive is physically possible if the above inequality is true.
Disprove this if you can...
There is no such mechanism proposed.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/15/2014 01:04 am
I guess it is impossible then  :(
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/15/2014 01:07 am
Mr Sonny White must know this... Whats going on?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: cordwainer on 06/15/2014 03:28 am
Just because there is know limiting mechanism that we can understand for a phenomenon yet proven does not mean that one does not exist. If the theoretical math is good then the burden of proof is in Sonny's court to prove that the phenomenon exists not to define the limits to that theory as yet. No doubt any limit to his QVCD phenomenon would be inherent within the discovery of the phenomenon itself as it is with most phenomenon.

Until we can measure quantum fluctuations we can't really know what it's energy limits are, most likely those limits would be somewhat like those of an open fluid dynamic system like the kinetic energy received from wind or water pressure. The amount of energy that could be efficiently extracted would depend on the QVPT cavity and the locally available zero point energy.

 It's similar to how a mag sail would work in operation, you need energy to charge the QVPT array or negative energy bubble but how much negative energy you can get into your bubble or how much kinetic energy you can wring out of a quantum fluctuation would be dependent on the size and efficiency of the array and the local energy within the locally overlapping zero-point field or extra-dimensional space where this phenomenon is actually emanating from.

Yeah, it's quite sci-fi sounding but not entirely outside the realm of theoretical physics. There are good reasons within our understanding of the Standard Model to believe that extra-dimensions, Dirac seas, zero point fields, exotic matter or other phenomenon could exist and produce the "quantum fluctuations" that Dr. White is looking for. 
Title: Re: No Joke: NASA Working on Warp Drive
Post by: cordwainer on 06/15/2014 03:51 am
I would also point out that saying quantum fluctuations are somehow fanciful in and of themselves would be tantamount to calling into question the Standard Model's understanding of the early universe, the Big Bang and inflationary theory. Quantum fluctuations are one of the many as yet unexplained phenomenon scientists use to explain the inexactness we currently see within the Standard Model. Hmm, sort of like dark matter, dark energy and a non-zero cosmological constant.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: 93143 on 06/15/2014 04:43 am
I've not been following the Q-thruster stuff too closely - is there a plausible story yet about how it doesn't violate conservation of energy? (a question that any purported reactionless drive needs to be able to answer)

does it abide by the photon rocket limit?
I too would like to know this...
There must be some mechanism that limits the Q-thruster/Woodward drive vehicle so that the energy supplied in accelerating it is always greater than
(http://upload.wikimedia.org/math/9/f/3/9f3d089c43d0ac712f710a8be8fd1aea.png)

Does anyone know what that mechanism is?

Short version:  just like with ordinary rockets, you have to take the reaction mass into account if you want to get a sensible answer.  An M-E thruster supposedly reacts against the rest of the mass in its lightcone via gravinertial radiation.  A Q-thruster supposedly reacts against transient particles created by quantum fluctuations; the particles may not persist, but the momentum has to go somewhere and presumably does...

If you only consider the kinetic energy of the thruster and vehicle, you can never solve the conservation equations consistently because a single-component kinetic energy is not Galilean-invariant (or Lorentz-invariant, if you insist on using relativity for your toy problems).  You're trying to analyze half of an open system and naturally enough getting garbage.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/15/2014 01:39 pm
Thanks for your comments. My stating 'Prove it's impossible' was misguided.
I guess I just want some form of propellant-less drive to be possible and my limited knowledge of physics led me to the most obvious objection to it. I hoped there must be an easy answer.
93143 hints at a solution to my naive analysis but doesn't really go into detail. I suspect because he too doesn't understand the 'toy' problem enough.
He states "An M-E thruster supposedly reacts against the rest of the mass in its lightcone via gravinertial radiation."
The mass in the thruster's lightcone once it is switched on? This is obvious nonsense. The lightcone of the thrusters particles since they were 'created'? That would include the entire (observable?) Universe then.
After doing some further reading the KE of the postulated vehicle is supposed to come from the mass-energy of the causally connected Universe... That's one hell of an open system, or is it a closed system?
I guess the jury is still out on this.
I await news of more research with interest.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: john smith 19 on 06/15/2014 02:39 pm
Thanks for your comments. My stating 'Prove it's impossible' was misguided.
I guess I just want some form of propellant-less drive to be possible and my limited knowledge of physics led me to the most obvious objection to it. I hoped there must be an easy answer.
93143 hints at a solution to my naive analysis but doesn't really go into detail. I suspect because he too doesn't understand the 'toy' problem enough.
He states "An M-E thruster supposedly reacts against the rest of the mass in its lightcone via gravinertial radiation."
The mass in the thruster's lightcone once it is switched on? This is obvious nonsense.
Wrong.

http://en.wikipedia.org/wiki/Light_cone
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The lightcone of the thrusters particles since they were 'created'? That would include the entire (observable?) Universe then.
After doing some further reading the KE of the postulated vehicle is supposed to come from the mass-energy of the causally connected Universe... That's one hell of an open system, or is it a closed system?
I guess the jury is still out on this.
I await news of more research with interest.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/15/2014 02:44 pm
How is it wrong? I understand what a lightcone is. Example: If I switch on a ME thruster on Earth, after 1/10 sec the Moon is not in the thrusters lightcone.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/15/2014 05:40 pm
[...] A Q-thruster supposedly reacts against transient particles created by quantum fluctuations; the particles may not persist, but the momentum has to go somewhere and presumably does...


That's why I asked if there's a "plausible story". This is not a plausible story, this is at the level of waggling your fingers an going 'oooh, magic!'

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If you only consider the kinetic energy of the thruster and vehicle, you can never solve the conservation equations consistently because a single-component kinetic energy is not Galilean-invariant (or Lorentz-invariant, if you insist on using relativity for your toy problems).  You're trying to analyze half of an open system and naturally enough getting garbage.

you can certainly analyse the energetics of partial systems - in terms of inequalities. Unless the kinetic energy of the exhaust is negative? Or the device is extracting energy from the quantum vaccuum. Either of which would be rather significant discoveries.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: SteveKelsey on 06/15/2014 10:10 pm
After doing some further reading the KE of the postulated vehicle is supposed to come from the mass-energy of the causally connected Universe... That's one hell of an open system, or is it a closed system?

No. It's simply a closed system the size of the cosmos. There, I hope that helps.  ;D
Title: Re: No Joke: NASA Working on Warp Drive
Post by: 93143 on 06/16/2014 12:47 am
[...] A Q-thruster supposedly reacts against transient particles created by quantum fluctuations; the particles may not persist, but the momentum has to go somewhere and presumably does...


That's why I asked if there's a "plausible story". This is not a plausible story, this is at the level of waggling your fingers an going 'oooh, magic!'

I'm not claiming the Q-thruster works.  I'm claiming that if it works, it will conserve momentum by reacting against something, and thus any conservation argument that neglects the reaction mass is invalid.  Like the M-E thruster, it is not a "reactionless" drive; it doesn't claim to produce force out of nowhere.

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If you only consider the kinetic energy of the thruster and vehicle, you can never solve the conservation equations consistently because a single-component kinetic energy is not Galilean-invariant (or Lorentz-invariant, if you insist on using relativity for your toy problems).  You're trying to analyze half of an open system and naturally enough getting garbage.

you can certainly analyse the energetics of partial systems - in terms of inequalities. Unless the kinetic energy of the exhaust is negative? Or the device is extracting energy from the quantum vaccuum. Either of which would be rather significant discoveries.

It's all about the frame of reference.

http://talk-polywell.org/bb/viewtopic.php?f=10&t=2215&start=1995#p105085

If the reaction mass is moving in the same direction as the thruster with respect to an observer, the kinetic energy of the "exhaust" can indeed be below its initial state.  This is how the Oberth effect works...

And yes, the whole point of the Q-thruster is that it exchanges momentum and energy with the quantum vacuum.  Just as the point of the M-E thruster is that it exchanges momentum and energy with all matter within its Hubble sphere (there; happy?).

Whether the proposed physical mechanism of each thruster makes sense is a separate question, but the fact remains that you cannot demonstrate anything either way by complaining about the kinetic energy of the spacecraft while ignoring the reaction mass.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: KelvinZero on 06/16/2014 09:31 am
I too would like to know this...
There must be some mechanism that limits the Q-thruster/Woodward drive vehicle so that the energy supplied in accelerating it is always greater than
(http://upload.wikimedia.org/math/9/f/3/9f3d089c43d0ac712f710a8be8fd1aea.png)

Does anyone know what that mechanism is?

If we are going to consider FTL and reactionless drives, we shouldn't be scared of a little free energy. :)

When I was talking about paradoxes before, My point wasn't that paradoxes mean it is not worth investigating. Its more that you just simply absolutely have to explore how paradoxes get resolved within whatever proposal, or you simply have no idea what you have. It would be the same as saying, "I have produced FTL, but I dont know how it behaves." The claim would not have any real meaning.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: francesco nicoli on 06/16/2014 10:06 am
just because Dr white was not satisfied with the sigma level of his data and analysis does not mean he reported negative results. he said quite the opposite. (that the preliminary results were suggestive that he had detected a warp and he was encouraged by them) that is... unless there was a report after the one i saw.

"Not satisfied with the sigma level" means statistical analysis of the data did not support the conclusion.  That's a negative result.  At least it's a negative result to real scientists.  White not reporting it doesn't mean the result wasn't negative.  A preliminary result is what you get when you are doing a preliminary test, not when you do a rigorous experiment and it doesn't give the results you like.

(Also, why is it that some parts of your post follow standard capitalization rules and some do not?  Do you not realize that standard capitalization lets people read more quickly?  By putting a little more effort into generating your content, you will be aiding the many people you are asking to read it by posting.)


not really. one thing is sample significance, the other is statistical significance. You can have positive results but statistically not significant- ie results are correct for the sample but cannot be generalized because you might have errors in sample selection. positive but statistically insignificant results do not imply that the study is to be thrown away: statistical significance can be improved by largerly increase the sample, so in this case the testbed experiments run.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/16/2014 10:16 am
I'm not claiming the Q-thruster works.  I'm claiming that if it works, it will conserve momentum by reacting against something, and thus any conservation argument that neglects the reaction mass is invalid.  Like the M-E thruster, it is not a "reactionless" drive; it doesn't claim to produce force out of nowhere.

[...]

And yes, the whole point of the Q-thruster is that it exchanges momentum and energy with the quantum vacuum.  Just as the point of the M-E thruster is that it exchanges momentum and energy with all matter within the Hubble sphere (there; happy?) of the thruster.

The M-E thruster is a good example, I think. That does have a "story" about its method of operation - there's meat on the bones, if you will: you can take a view on the plausibility of Gravinertial theory or Wheeler-Feynman absorber theory. You (or at least Woodward) can do sums with it.

I was hoping that the Q-thruster has something like that. If it extracts energy from the quantum vacuum, how does it do it? does this imply a state transition in the quantum vacuum (like a false vacuum)? what is the four-momentum of the exhaust? how do these quantities vary under a change of reference frame? (you can quite easily do this for an ordinary rocket and see the frame velocity dependence cancel out)

Unless there's a "story" that addresses these questions, you can't talk intelligibly about whether might work or not, there's simply insufficient data.

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but the fact remains that you cannot demonstrate anything either way by complaining about the kinetic energy of the spacecraft while ignoring the reaction mass.

I disagree, obviously. I'll go into my thinking in more detail if you want, but I've got no skin in this game so I'm content to let it lie.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: DMeader on 06/16/2014 01:19 pm
What annoys me most about ill-informed and misleading stories like the one that spawned this thread is than now the general media has picked up on it, and the general public is getting the idea that in a couple of years we'll be flying around in NASA's new warp ship.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: JohnFornaro on 06/16/2014 01:27 pm
http://rationalwiki.org/wiki/Statistical_significance

You may find the section on 'The problems with statistical significance' interesting reading

Thanks for the link to the oracle.

An abuse of statistics is when journalists or certain agenda pushers ignore the concept of significance entirely - leading to false information being given out to people. (http://rationalwiki.org/wiki/Statistical_significance)

Note that reciting a definition of "statistical abuse" is by no means an accusation of the practice of pseudoscience.

... it would mean more space and mass allowances for equipment and materials for use at the various destinations such a craft could get to right here in this solar system.

"Would" being the only operative term.  "Everybody" knows about the benefits of increasing the speed of the spacecraft.

Oh, it's the same old capacitors/reactionless shtick. Next thread!
Granted. It wont work if my inequality above us violated, but why not in general. Can you prove such a thing is impossible?

You know that "proving the impossible" is a fool's errand.

First, prove that your "inequality" is not violated by using the information provided by Mr. White.  There is no point in further discussion otherwise.

Mr Sonny White must know this... Whats going on?

Scientainment.

'Prove it's impossible' was misguided.

Good job.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: 93143 on 06/16/2014 09:34 pm
Quote
but the fact remains that you cannot demonstrate anything either way by complaining about the kinetic energy of the spacecraft while ignoring the reaction mass.

I disagree, obviously. I'll go into my thinking in more detail if you want, but I've got no skin in this game so I'm content to let it lie.

It seems like we're more or less on the same page.  Could you elaborate on this?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/17/2014 10:37 am
It seems like we're more or less on the same page.  Could you elaborate on this?

Sure, here's what I'm thinking:

Let's consider the simple energy balance between energy in and energy out. For the moment I'll ignore spooky quantum effects, but I'll come back to them.

The only energy input into the system is electrical energy into the drive: (assumption 1)

Eelec ≥ ΔKEvehicle + ΔKEexhaust   (1)

This has to be true whatever frame you analyse it in.

ΔKEexhaust ≥ 0, because we're assuming that you have no effect on the exhaust plume previously emitted, and the KE of the extra exhaust during our time step is axiomatically positive (assumption 2)

(aside: why is this not true for rockets? because from a sufficiently boosted frame it looks like the vessel is decelerating its propellant. So, if you think in terms of the propellant, ΔKEpropellant can be negative. Here, however, the total mass of the vehicle does not change. People complain about "reactionless" drives, but the real problem is a "propellantless" one.)

given this, if we write:

Eelec ≥ ΔKEvehicle  (2)

we can see that if (2) is false, (1) must also be false. As ΔKEvehicle is frame-dependent and Eelec is not, you can always choose a frame where (2), and thus (1), is not true.



How can we get around this? let's consider our two assumptions.

break assumption 2: the "exhaust" has negative Kinetic Energy. I don't even know what this means ;). Negative exhaust mass maybe?

break assumption 1: there is some other energy input into the system. Presumably from the "quantum vacuum". The observed magnitude of this energy input will vary depending on the relative velocity of the observer, which is... odd. Reminds me weirdly of black hole complementarity, actually. If there's energy coming from the quantum vacuum, what does this imply about the energy levels of the vacua?


So there it is. I'd like an explanation of which of these assumptions is broken and how.

(edited for typos)
Title: Re: No Joke: NASA Working on Warp Drive
Post by: 93143 on 06/17/2014 07:57 pm
ΔKEexhaust ≥ 0, because we're assuming that you have no effect on the exhaust plume previously emitted, and the KE of the extra exhaust during our time step is axiomatically positive (assumption 2)

I believe the problem lies with assumption 2.

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(aside: why is this not true for rockets? because from a sufficiently boosted frame it looks like the vessel is decelerating its propellant. So, if you think in terms of the propellant, ΔKEpropellant can be negative. Here, however, the total mass of the vehicle does not change. People complain about "reactionless" drives, but the real problem is a "propellantless" one.)

The hidden assumption here seems to be that the reaction mass for a "propellantless" thruster is initially stationary with respect to the observer.

As a trivial counterexample, consider a 1500 kg car on the highway, moving at 30 m/s.  You (the observer) are in another car moving at 35 m/s in the other direction.  The first vehicle is accelerating at 0.5 m/s², exerting a 2000 N force on the road (60 kW, or ~80 hp) in order to do so (yes, this includes air resistance).  As a result of this, from your perspective its kinetic energy increases at 48.75 kW, while the kinetic energy of the Earth decreases at 70 kW.

If I had done this example without air resistance, the first car would have been gaining more kinetic energy than it expended in shaft work.  In fact, in this example the air resistance alone soaks up more energy than the car expends in shaft work...

It's not the fact that a rocket expends propellant that makes the Oberth effect work; it's the fact that the propellant is initially moving at the same velocity as the rocket.

...

It seems to me that if a given space drive obeys Lorentz covariance, as M-E seems to and as the Q-thruster had better if it's going to have a shot at being physically plausible, the effective mean velocity of the propellant should be tied to the velocity of the thruster, not that of the observer.  At worst, it would be tied to neither, which seems more plausible with M-E than with the Q-thruster (except that the M-E equation doesn't show any dependence on the mean velocity of the distant matter; indeed it doesn't directly reference the distant matter at all).

I'm not familiar enough with quantum mechanics to say much about the Q-thruster, but in the case of M-E it isn't obvious how such a coupling would work.  Still, while preferential interaction based directly on the velocity of the distant matter in question doesn't seem to make sense, I suspect that the peculiar velocity of the thruster (velocity minus comoving velocity) could result in a preferential direction of interaction, which in an expanding universe is effectively the same thing...

Do not quote me on this as I have not done the math...
Title: Re: No Joke: NASA Working on Warp Drive
Post by: IslandPlaya on 06/17/2014 08:36 pm
It seems reasonable that the reaction mass for a "propellantless" thruster is in an inertial reference frame. So yes, it is stationary with respect to the observer. If this were not the case then you would run into all sorts of trouble with Special Relativity.
So the hidden assumption is in fact true IMHO.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/17/2014 10:35 pm
The hidden assumption here seems to be that the reaction mass for a "propellantless" thruster is initially stationary with respect to the observer.

kinda - I'm assuming the reaction mass is being magically handwaved into existence :)
In fairness, that's what descriptions of the device sound like..

Like I said, there's something going on - I'd just like a hypothesis as to what that something is.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: 93143 on 06/17/2014 11:50 pm
Well, that's no good...

Why are we so concerned about conservation of momentum and energy if conservation of mass isn't being respected?

It seems (from the references on Wikipedia) that White is trying to leverage the dynamic Casimir effect or something like that, and he asserts that there will be a "wake" of some sort.  This is not something out of nothing; it is at most a zero-point energy device.  And I would imagine that if the principle of operation turns out to be physically consistent, the phenomenon will be linked to the thruster's frame of reference due to Lorentz covariance - how it sees the vacuum shouldn't depend on its velocity as seen by an observer.

So the question isn't so much "how does the Q-thruster conserve energy?" as "how does the Q-thruster work?".  If you can answer that, it should become evident whether or not it has conservation issues.  If you can't answer that, you have no basis for bringing in stuff like assumption 2.

@IslandPlaya:  Just because something's in an inertial reference frame doesn't mean it's in your inertial reference frame.  Take a look at my example with the cars.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/18/2014 01:06 pm
Well, that's no good...

Hey, it's not my job to explain it, merely to show that an explanation is required :D

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Why are we so concerned about conservation of momentum and energy if conservation of mass isn't being respected?

mass is not a conserved quantity.

Sure, I could have added the mass-energy of the exhaust to the right hand side of the inequality, but as that is also axiomatically positive (even for hypothetical particles of negative mass) nothing changes. Besides, it's not clear to me that the device is creating real (i.e. mass-shell) particles, so saying they have mass is the assumption, not the other way round.


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It seems (from the references on Wikipedia) that White is trying to leverage the dynamic Casimir effect or something like that, and he asserts that there will be a "wake" of some sort.  This is not something out of nothing; it is at most a zero-point energy device.

When I'll have time I'll have to follow up on these references, because that sounds like word salad to me. The phrase "at most a zero-point energy device" is also rather eyebrow-raising, given that - according to our current understanding - such a thing is physically impossible. (That was my "assumption 1"). The significance of a zero point energy device would knock a poxy rocket engine into a cocked hat!

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So the question isn't so much "how does the Q-thruster conserve energy?" as "how does the Q-thruster work?".

As a physicist, those questions are one and the same.

Quote
If you can't answer that, you have no basis for bringing in stuff like assumption 2.

Once again, it's not my job to explain it, merely to show that an explanation is required.

Still, I think the "assumption" that the kinetic energy of a moving object is positive is a pretty well grounded one!

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@IslandPlaya:  Just because something's in an inertial reference frame doesn't mean it's in your inertial reference frame.  Take a look at my example with the cars.

Actually, I think you're both right. I think the "initial velocity of the quantum vacuum" (and I put the phrase in quotes because I'm not even convinced it's meaningful) has to be zero in every inertial frame, otherwise you can say goodbye to the Principle of Relativity. This means that a stationary observer and an observer on the vehicle will "disagree", but that's not necessarily a problem.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: 93143 on 06/18/2014 09:48 pm
mass is not a conserved quantity.

If the thruster has to convert energy to matter before throwing it backward, its thrust efficiency will be worse than that of a photon rocket, not better.  (And even then, the energy will have to be either stored in or transmitted to the spacecraft, so you can account for its momentum before it's operated on by the thruster, and assumption 2 still fails.)  The Q-thruster is only interesting for propulsion if either (a) it magically generates propellant out of nowhere, or (b) the propellant exists in some form external to the spacecraft before being acted on.

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Sure, I could have added the mass-energy of the exhaust to the right hand side of the inequality, but as that is also axiomatically positive (even for hypothetical particles of negative mass) nothing changes. Besides, it's not clear to me that the device is creating real (i.e. mass-shell) particles, so saying they have mass is the assumption, not the other way round.

Something has to absorb the momentum.  And it can't be created out of nothing or conservation is trivially violated.  The requirement that whatever it is exist in some form before it is operated on by the thruster renders assumption 2 invalid, because its kinetic energy in its initial state is not necessarily zero from the perspective of an arbitrary observer.

If the transient QVF particles being immediately acted on don't persist, I would expect an M-E-like ultimate transfer of momentum to something that does.  If they do, I would expect their new mass-energy to be subtracted from something else (like with Hawking radiation), and the whole system to conserve momentum and energy in all reference frames.

...I was pretty sure that a particle had to have mass (not necessarily rest mass) in order to have momentum...?

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So the question isn't so much "how does the Q-thruster conserve energy?" as "how does the Q-thruster work?".

As a physicist, those questions are one and the same.

As an aerospace engineer, no they are not.

If you've got an idea, you have to tell me how it works in detail before I can figure out if your explanation makes sense.  I can't just make an arbitrary assumption (especially one that violates the known laws of physics) and require your explanation to conform to it.  The most I can do is speculate that if your idea works, it will respect the known laws of physics.

Conversely, it is certainly possible to describe a device that conserves energy without being physically plausible...

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Still, I think the "assumption" that the kinetic energy of a moving object is positive is a pretty well grounded one!

But that's not what you assumed.  You assumed that the kinetic energy of the object was lower before it was accelerated than afterwards, which is not at all the same thing.

Or rather, that the object didn't exist in any form before being accelerated...

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@IslandPlaya:  Just because something's in an inertial reference frame doesn't mean it's in your inertial reference frame.  Take a look at my example with the cars.

Actually, I think you're both right. I think the "initial velocity of the quantum vacuum" (and I put the phrase in quotes because I'm not even convinced it's meaningful) has to be zero in every inertial frame, otherwise you can say goodbye to the Principle of Relativity. This means that a stationary observer and an observer on the vehicle will "disagree", but that's not necessarily a problem.

It's only not a problem if you don't take it as validating assumption 2, which is what he seemed to be doing - casting the observer as "right".

I would say that the vacuum being acted on must look different to the thruster and to the observer (ie: stationary to both, where a classical mind would expect a Galilean frame transform), but for the same reason, any effect resulting from the operation of the drive would have to transform properly between reference frames.

I'm not at all convinced the Q-thruster is a good idea, but admittedly I haven't studied it much, and my QM is pretty rudimentary and mostly qualitative...
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/19/2014 10:15 am
Alright, I went and read the references. Someone seriously published those? It's nothing more than a string of sciencey-sounding non-sequiturs.

Nothing to see here, move along.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: DMeader on 06/19/2014 02:31 pm
Alright, I went and read the references. Someone seriously published those? It's nothing more than a string of sciencey-sounding non-sequiturs.

Nothing to see here, move along.


Quite a lot of that around. Sad thing is that so many people take things like that very seriously
Title: Re: No Joke: NASA Working on Warp Drive
Post by: 93143 on 06/19/2014 07:06 pm
Alright, I went and read the references. Someone seriously published those? It's nothing more than a string of sciencey-sounding non-sequiturs.

Nothing to see here, move along.


...so, no response to my objections to your argument?

I've repeatedly tried to make it clear that I don't expect much from the Q-thruster.  I actually read one of White's warp papers, and as far as I can tell the concept of "boost" he uses is inconsistent with Galilean relativity, never mind the more modern kind...

But we weren't discussing that.  The subject was a more general argument about conservation in propellantless thrusters.  I assert that you have made an invalid assumption, and you haven't adequately addressed that.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/19/2014 08:46 pm
...so, no response to my objections to your argument?

Sorry, I have a short attention span :)

My argument is a back-of-the-envelope straw man - it's meant to have holes poked in it. Nevertheless, I think it illustrates where any new physics must lie, and what the potential problems are. I'm satisfied with that.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Ilinca Sergiu on 06/20/2014 03:40 pm
...so, no response to my objections to your argument?

Sorry, I have a short attention span :)

My argument is a back-of-the-envelope straw man - it's meant to have holes poked in it. Nevertheless, I think it illustrates where any new physics must lie, and what the potential problems are. I'm satisfied with that.

If I understand correctly Q -thruster it's Oberth effect + (quantum vaccum). If so it looks like my engine (magnetic jet engine on Oberth effect) but I have no (quantum vaccum).
Here is my engine. Maybe something will help.
In short, I use high acceleration of  nozzles for transformation Isobaric process of jet in isochoric (high pressure).
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Hanelyp on 06/20/2014 05:13 pm
I actually read one of White's warp papers, and as far as I can tell the concept of "boost" he uses is inconsistent with Galilean relativity, never mind the more modern kind...
My assessment as well.  If you're going to accelerate to X then apply a boost to X*Y, why not apply the boost to an arbitrary rest frame moving -X relative to your original motion?  What makes your frame before accelerating special?

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... The subject was a more general argument about conservation in propellantless thrusters. ...
It seems to me that an ME thruster might perform as described if it preferentially coupled to remote mass at low relative velocity.  But that's a characteristic I'm not seeing described by proponents of the device.

If I'm understanding the effect as described, coupling equally to all remote mass, simply driving a capacitor in an AC tank circuit would seem predicted to produce a measurable momentum transfer effect without pushing it back and forth, unless you happened to be operating at the average rest frame of the remote mass involved.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: the_other_Doug on 06/22/2014 10:04 pm
Does the theory behind the Alcubierre warp drive make any predictions about physical effects that would be observable in "normal" space as the warp bubble passed through it?

It seems to me that if the Alcubierre drive can be made to work with technology only a century or two beyond our own, this would imply that other technological civilizations would indeed be using it throughout the galaxy.  If there are specific signatures we can search for that are detectable to remote sensing, I'm pretty certain that the one datum which would drive us (pardon the pun) into developing warp technology would be to see incontrovertible proof that we have neighbors who are already using it...

-Doug (with my shield, not yet upon it)
Title: Re: No Joke: NASA Working on Warp Drive
Post by: QuantumG on 06/22/2014 10:11 pm
Does the theory behind the Alcubierre warp drive make any predictions about physical effects that would be observable in "normal" space as the warp bubble passed through it?

Nah.. it's entirely a local effect. So, unless their ships are of astronomical size, we'd have to know exactly where to look at exactly the right time.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: the_other_Doug on 06/22/2014 10:23 pm
I know that we don't see any obvious signs, like big neon signs announcing the off-ramps...  What I don't know is whether anyone has seriously looked at what physical, normal-space signature(s) might result from the Alcubierre equations, and if so, has anyone actually looked for such signature(s)?

I have a hard time believing that a standing wave of time/space moving at superluminal velocities through normal space, containing a bubble of normal spacetime, can just pass on by without leaving *any* indications it had ever been there.  Even if it's just an abnormal number or energy level of background neutrinos or something.  There is enough energy being pumped into this warp bubble to outshine a galaxy if let go as a simple explosion -- I'd have to think that, at least at a particles-and-fields level, that something is out there and capable of being detected.

IslandPlaya's "we see nothing" is meaningless, since we very likely don't even know what we're looking for as far as physical indications of warp technology being used.  Heck, maybe we have seen very obvious indications, we just don't know them for what they are.

-Doug (with my sield, not yet upon it)
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/22/2014 11:31 pm
It seems to me that if the Alcubierre drive can be made to work with technology only a century or two beyond our own

Unless "exotic matter" doesn't actually exist..
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/23/2014 03:16 am
it is my understanding that the exotic mass/energy is needed to shape the deformation of the local space/time fabric; i.e; warp space.

we can make negative energy albeit a tiny bit for a tiny time with tremendous expenditure of more mundane energy. e.g; squeezed light has a tiny bit of time where a tiny bit of it can be considered negative energy. so it's not out of the question that we could make enough of it with the right type of amplifier circuitry.

but what says negative energy or mass is even necessary? what if it isn't? consider yourself standing on a sphere with the mass and gravity of earth. the gravity holding you down is sometimes represented as two curved lines and called a gravity well. but since gravity has to do with the geometry of space or the shape of space  presumably anti gravity could be represented by an inverted set of lines above the attracted mass.

so if you were standing on such a sphere and suddenly a larger sphere with more gravity were positioned 6 inches above your head you would have a larger gravity well pulling you against the gravity of the smaller sphere. again this would represent curvature of space in the opposite configuration as the well you stand in.

again this new gravity source bends space opposite to the one you are in on the smaller sphere. it's not anti-gravity but in a way it is. it's not negative mass but in a way it is. the effect, it seems to me, would be to do to space what we want negative energy and negative mass to do for the warp drive.

ok there are still problems like inconvenient to move actual masses around like this let alone propel them in tandem anywhere, or to use energy for the same effect would seem to require extravagant impossible amounts of energy. but engineering problems aside why wouldn't regular energy or mass be able to be arranged in such a way it could serve the function we want?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/23/2014 10:39 am
but what says negative energy or mass is even necessary?

*shrugs* Miguel Alcubierre says so.

I don't pretend to understand the Alcubierre metric in all its gnarly detail - GR is not my speciality - but the gravity gradient within the "bubble" is locally flat; the motion is explicitly not caused by acceleration due to gravity.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/24/2014 05:20 pm
but what says negative energy or mass is even necessary?

*shrugs* Miguel Alcubierre says so.

I don't pretend to understand the Alcubierre metric in all its gnarly detail - GR is not my speciality - but the gravity gradient within the "bubble" is locally flat; the motion is explicitly not caused by acceleration due to gravity.

I am not disagreeing with you. i am not being negative. i think my objection is a positive thing.

I just don't see how it's necessary. deformation of space is deformation of space. positive and negative should be dependent on how you are looking at it. i think any geometry could be created because the aspect of the deformation changes depending on spatial relationship and point of view. we are taught there is no special direction in space; no favored position. so whether space is deformed left to right or up or down depends on where you are and where you are looking. if there is a gravitational mass "above" you you will fall up. if it is below you you will fall down. both are the result of positive masses. the only thing that has changed is your orientation.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: scienceguy on 06/24/2014 05:26 pm
The math of Alcubierre's metric says the mass should be negative. That's just what the math says.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Vultur on 06/24/2014 05:33 pm
Is the negative energy needed for the expanded space behind the spacecraft? If so, does cosmic inflation (if correct of course) show that it's physically possible?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/24/2014 05:38 pm
The math of Alcubierre's metric says the mass should be negative. That's just what the math says.

well why wouldn't the math take on the opposite sign when formulated for a different reference frame?

relativity is pretty confusing once you start to figure  out what happens from different points of view. the people at the origin see some thing different from the people in the travelling refernce frame. and i think both are different from someone looking on from the sidelines and from some one traveling in parallel or in the opposite direction.

i recently had to spend several posts telling people that time does not alter from the point of view of the starting point with reference to time dilation. several people were arguing vehemently that the stationary observers would see a relativistic trip to alpha centauri take thousands of years because they were applying time dilation effects to what the stationary observers back home would see. they were so convinced they were right that they argued for pages in the thread to that effect. i asked if when we look at alpha centauri are we seeing it as it was 4.3 years ago or thousands of years ago since photons travel at light speed.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: hop on 06/24/2014 09:02 pm
well why wouldn't the math take on the opposite sign when formulated for a different reference frame?
Have you read and understood Alcubierre's paper (http://arxiv.org/abs/gr-qc/0009013)? Not just "I think I get the general idea" but actually understood the mathematical arguments that make it work?

If not, then it's hard to see the point of this discussion. If you do have sufficient understanding of GR to follow the paper, and still believe you have a "warp drive" solution that doesn't require exotic matter, you should probably publish it... assuming you have the math to back it up, but if you don't, then why would you believe you had a solution?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/24/2014 09:17 pm
well why wouldn't the math take on the opposite sign when formulated for a different reference frame?
Have you read and understood Alcubierre's paper (http://arxiv.org/abs/gr-qc/0009013)? Not just "I think I get the general idea" but actually understood the mathematical arguments that make it work?

If not, then it's hard to see the point of this discussion. If you do have sufficient understanding of GR to follow the paper, and still believe you have a "warp drive" solution that doesn't require exotic matter, you should probably publish it... assuming you have the math to back it up, but if you don't, then why would you believe you had a solution?
I base my argument on the fact that i think a physically inverted gravity well is the same in all particulars (effects) as a negative gravity field. the gradient should do the exact same thing as a deformation caused by negative mass or energy. the question is...is that true or not? if not why not?
Title: Re: No Joke: NASA Working on Warp Drive
Post by: momerathe on 06/25/2014 09:26 am
I base my argument on the fact that i think a physically inverted gravity well is the same in all particulars (effects) as a negative gravity field. the gradient should do the exact same thing as a deformation caused by negative mass or energy. the question is...is that true or not? if not why not?

that I can answer: the sign of the second differential of the potential will be opposite between the positive and negative energy case.
Title: Re: No Joke: NASA Working on Warp Drive
Post by: Stormbringer on 06/25/2014 04:38 pm
I base my argument on the fact that i think a physically inverted gravity well is the same in all particulars (effects) as a negative gravity field. the gradient should do the exact same thing as a deformation caused by negative mass or energy. the question is...is that true or not? if not why not?

that I can answer: the sign of the second differential of the potential will be opposite between the positive and negative energy case.

ok. you know that alcubierre related graphic that represents space in front of around and behind a space ship? i am not saying that gravity is what deforms that space in the graphic. but it seems that since gravity (the presence of mass, etc) does deform space in the same way, and poop always runs down hill, if a gravity well were to pull "up" on space behind the ship then the ship would slide downhill from that well and if space were pulled in the opposite direction in the front of the ship it would also roll down that hill as well.

really i guess the issue is i do not see how a properly positioned gravitational field would not have the same effect on the ship. i am not talking about mathematical equations and such. i know that the signs for negative mass energy are obviously the opposite of positive or normal matter.  i am going by what the negative matter/energy is supposed to do physically to space for the concept.

in my mind the most tenuous iffy part of what i am saying is not an imparted motion due to gravity. its; is this slide equivalent to expanding space behind the ship and contracting it before the ship?