Marc Millis is once again in the media, this time interviewed by a BBC crew in a show about controlling gravity. The impetus is an undertaking I described in the first chapter of Frontiers of Propulsion Science, Project Greenglow. The former head of NASA’s Breakthrough Propulsion Physics project and founding architect of the Tau Zero Foundation, as well as co-editor with Eric Davis of the aforesaid book, Millis has some thoughts on how we discuss these matters in the media, and offers clarifications on how work on futuristic technologies should proceed.
by Marc Millis
A BBC ‘Horizons’ episode will air next Wednesday, March 23 (8pm UK) about the Quest for Gravity Control. The show features, among other things, an interview with myself about my related work during NASA’s Breakthrough Propulsion Physics project and thereafter with the Tau Zero Foundation. Quoting from an advertisement for the show, Project Greenglow – The Quest for Gravity Control:
This is the story of an extraordinary scientific adventure – the attempt to control gravity. For centuries, the precise workings of gravity have confounded the greatest scientific minds – from Newton to Faraday and Einstein – and the idea of controlling gravity has been seen as little more than a fanciful dream. Yet in the mid 1990s, UK defence manufacturer BAE Systems began a ground-breaking project, code-named Greenglow, which set about turning science fiction into reality. On the other side of the Atlantic, NASA was simultaneously running its own Breakthrough Propulsion Physics Project. It was concerned with potential space applications of new physics, including concepts like ‘faster-than-light travel’ and ‘warp drives’.
With such a provocative topic, it can be difficult to extract the realities between the more entertaining extremes of delusional crackpots and pedantic prudes. We’ve not yet seen the episode to know what is, or is not, covered. For those interested in the more substantive realities – at least to the level of our own perceptions – here is a short status report.
First, there are several lines of inquiry in general physics. This includes Einstein’s theory, which describes gravity in terms of warped spacetime; high-energy particle experiments that explore the unification of all the fundamental forces at higher energies; and cosmological observations on the role of gravitation and quantum phenomena on the formation of the universe. Such investigations are aimed at understanding nature for its own sake, rather than for the ambition of controlling gravitation.
One example of applying this knowledge to the challenge of controlling gravity goes back to the early 1960’s with Robert L. Forward’s “Dipole Gravitational Field Generator ” (Am. J. Phys., Vol. 31, 1963, pp. 166-170). In this and subsequent works by others, it has been shown that spacetime can be warped to produce “designer” gravitational fields. Such warps require enormous energy densities and/or stresses/pressures of either moving matter, extreme electromagnetic fields, or specially modified quantum vacuum energy. This has not yet led to any practicable devices.
When one shifts the focus from general physics to a utilitarian challenge (say, controlling gravitation for propulsion or for zero-gravity recreational rooms), two important points come into play:
- Having a desired application can taint one’s objectivity, since there is a desire for the results to turn out a particular way. This makes it harder to conduct the work with the rigor and impartiality needed to get reliable results. It is too easy to become either overly eager or pedantic. Hence, a higher degree of self-discipline is required when conducting application-specific research.
- By focusing on an application instead of for general knowledge, new pathways toward solving the lingering unknowns of science are created. In the first step of the scientific method, where one defines the problem to be solved, how that problem is defined then casts a unique perspective from which data will be collected and interpreted. It changes the way to look at the problem.
In 2009, Eric Davis and myself, working with over a dozen contributing authors, compiled a book about the various approaches for controlling gravitation and faster-than-light flight. By contrasting the make-or-break issues of these goals with known physics, the book identifies where next to concentrate research. It is still too soon to know if such breakthroughs will ever be achievable, but such application-specific research can now commence. Chapters 3 through 13 cover the topic of controlling gravity for space drives, while chapters 14 through 16 address faster-than-light flight:
– M. G. Millis and E. W. Davis (eds.), Frontiers of Propulsion Science, Progress in Astronautics and Aeronautics, Vol. 227, AIAA Press, Reston, VA, 2009, 2nd printing 2012.
Subsequent condensations have been published as:
– M. G. Millis (2012), “Space Drive Physics, Introduction & Next Steps,” JBIS, Vol. 65, pp. 264-277. From this, it appears that the next line of inquiry deals with the nature of inertial frames. Inertial frames are the reference frames upon which the laws of motion and the conservation laws are defined, yet it is still unknown what causes inertial frames to exist and if they have any deeper properties that might prove useful.
– E. W. Davis (2013), “Faster-Than-Light Space Warps, Status and Next Steps,” JBIS, Vol. 66, pp. 68-84. From this, it appears that the next lines of inquiry deal with the structure of the quantum vacuum in the context of warped spacetime. This includes closer examinations of the technological approaches to affect the quantum vacuum that might produce space warps.
While general physics has been making incremental progress to our understanding of gravitation, the other fundamental forces, and spacetime for centuries, research aimed at controlling gravitation for practical purposes is still in its infancy. In addition to the challenges of deciphering nature, the desire for a positive result makes it difficult to conduct the research with the impartiality needed to produce rigorous results. With a healthy blend of imagination, skepticism, and reason, progress will be made. One never knows how a media project will turn out, but my hope is that “Project Greenglow – The Quest for Gravity Control” will reflect these values.
I have a question and two comments.
Comments first. I would like to add two bullets to the two in your article:
1. saying something is impossible is a self-fulfilling prophesy that limits research
2. Trying to manage “blue-sky” research in the same manner as an applied development project, is also self-defeating, and a self-fulfilling prophecy of failure.
My question Marc: his thoughts on Sonny White’s work?
Sorry that this answer is long, but a curt reply would be a disservice to our readers and to Sonny.
Before I answer specifically about Sonny White’s work, I must explain the technique I use when deciding which ‘news’ to listen to. Instead of trying to decide if an IDEA has merit (which might be beyond my reflexive abilities), I look at HOW the researcher is going about the work. If the researcher is impartial and rigorous, then I keep reading. If they are posing a question without any desire for the answer to turn out a particular way (positive result or dismissal), then they demonstrate impartiality. If their methods are focused on making sure their findings are reliable (accurately interpreting nature) and fully disclosing those methods, then they are being rigorous. If they are impartial and rigorous, then their results will be trustworthy, regardless if it’s “good” or “bad” news for the quest of breakthrough spaceflight.
However… if they lack either impartiality or rigor, I turn away. This is because the result will be skewed by their wishes and the results will not be defensible. Even if the idea is a potential breakthrough, such sensationalist or sloppy work will not get us closer to a substantive result.
Here are some representative facts about Sonny’s work:
– Sonny has chosen to field his results via blogs, internal papers (not peer reviewed) and press interviews instead of through publications where the work will be scrutinized for rigor.
– Sonny names equipment after himself and coworkers (“White–Juday warp-field interferometer”).
– On the key component of his tests – the device to create the space warp – he has withheld disclosure.
– When inviting Sonny to submit a chapter to our book, where I asked him for an impartial assessment of Woodward’s Mach Thruster (of which he had done some tests), I got instead an advocacy pitch for one of Sonny’s theories.
So from the above, you can probably conclude that I no longer devote my time to following Sonny’s work. If he changes how he works – by being more impartial and rigorous and by subjecting his work to careful review before publishing, then I will reconsider.
Is White’s work basically the EMdrive or Cannea drive?
White has worked on warp drive claims, EM drive, Q thruster, and I think Cannae drive (frankly I lost track which is which). In all topics the symptoms are the same. I look forward to when the work shows a greater degree of impartiality and rigor, regardless of what is being worked on.
I get the impression he refers to both the Emdrive and Cannea drive as Q thrusters.
BTW, what do you think of the Woodward effect? Have you read his book?
Woodward published the theory that led him to begin experimental tests in the peer-literature. The theory is rooted in unsolved physics about the origins and properties of inertial frames. That is an important aspect, specifically of looking at physics that is both relevant and unsolved. The experimental results (some of which have also been scrutinized by peer reviews) have been so close to the edge of certainty for so long that my attention is waning. I’ve not read his book, but have read many of his papers and have had conversations with him. By now, if it were me, I’d trying and figure out some other aspect of the theory to test that might be easier to get clean data, or consider a different variation on the theory. I remain neutral on his line of inquiry. There are other branches of this theme that remain open too.
Thanks. After a while one gets tired of supposed new effects that are always in the noise.
The idea of research aimed at controlling gravitation for a specific practical purpose was perfectly described in ‘- We Also Walk Dogs’, which Robert Heinlein wrote in 1941. I read this story when I was about ten years old, and even then I figured out that it was implausible. You simply don’t get major scientific breakthroughs by trying to build a device for a particular purpose. You need pure science.
Hi Paul and Marc,
Marc, I’ve been interested in your work ever since I first found your old BPP website on NASA. Frontiers of Propulsion Science is a great book. I recommend it to anyone who doesn’t have a copy. When you feel the time is right, will you update it with new advancements?
Paul, a similar question to you – can we expect another book? Centauri Dreams whetted the appetite.
Finally to you both – if you know Nick Cook personally, have you heard of any plans to follow up his seminal The Hunt for Zero Point? That was an amazing detective story and a quite believable revelation, given his reputation at Jane’s Defence Weekly.
We starflight believers are lucky to have you both; your work is invaluable.
About a sequel to ‘Frontiers of Propulsion Science.’.. I would love to, or better yet, I would love to create a general audience version. BUT… I do not have the resources to make that happen yet. It’s not just a matter of my own time, but to serve the community with an accurate and impartial assessment of seeking breakthrough propulsion, I need lots of extra help from a variety of skill sets. I’m still disappointed about how many typos slipped through the second printing of the book, where we made a concerted effort to catch everything (some corrections must have gotten lost in the process). Editing, review, and formatting assistance, regardless of not being as glamorous as content, is a huge part of total value.
On Nick Cook’s, ‘The Hunt for Zero Point.” When I read Nick’s description of our interview, I was appalled by how much he read into it that was just not true. Knowing how wrong he got that, I have zero confidence about anything else written in that book. Or to evoke the criteria that I answered before in the context of Sonny White’s work, Nick failed at both impartiality and rigor.
Here’s what looks like a pretty decent review of Cook’s Book: http://www.salon.com/2002/08/05/zero_gravity/
It fits perfectly with what you say.
Marc and Eniac – thanks for the enlightenment on Cook’s book. Given Cook wrote for Jane’s Defence, I assumed trustworthiness and expected impartiality and vigor. What a huge disappointment.
Marc – I do hope those resources come your way in the next few years. A 5 to 7 year cycle of updated versions would be fantastic.
Paul – Any new book you write would be a gift. But what you’ve accomplished here on Centauri Dreams is indeed equal to a book.
Erik, I’ll let Marc handle Cook’s book — I know he has thoughts on that. I don’t have a book currently in the works, because I’ve found that this site has become a major part of my writing life. In a way, it’s the follow-up I had originally planned for the book. But things may change on this front, as I do have some book ideas I’d like to explore more fully. And thank you for your kind words.
We used to build machines unaware of the science behind them, most notably flying machines. It was very much trial and error.
Private R&D does very much the same today, with science being the spin-off rather than the goal. It is public research that generates the science that subsequently might generate a technology.
Gravity has proven intractable so far regarding making a device that can control it in some way, except at the most microscopic scale. At this point we really do need experimentally verified theory to understand whether we can control gravity with a machine or not.
I look forward to watching this show if the Beeb adds it to the iPlayer offerings.
Ron Evans of BAE Systems claimed last night on the programme that engineers don’t care if scientists say an invention is impossible, they just want to know if it works. But I don’t believe any engineer worth his salt would try and pass off an anti-gravity machine without understanding the physics behind it. If you don’t understand the physics, how can you have any confidence in making predictions about how it will behave under any given circumstance? Indeed, how can you even be sure that it uses anti-gravity?
The ironic thing is the programme did warn itself about this kind of unscientific thinking and it shows what a hodgepodge of a programme they made that they then went and ignored these warnings. At the beginning of the show Evans and the programme makers showed how a spinning gyroscope can create the illusion of anti-gravity, without ever explaining to the viewers the physics behind this illusion. Marc Millis went to great pains on the programme to explain that the scientific method is vital and, I’m paraphrasing him here and he might like to correct me on his quote, but he said something along the lines that by putting all these ideas and hypotheses to the scientific method and testing them rigorously, he and his team had taken an important first step just by doing that, and if that’s all he ever does in the field he’d be happy that he made that step. Yet the programme makers then ignored all of this to dive headlong into fanciful theories and peddle them as potentially real anti-gravity machines, trying to get us to root for them. Despite the EmDrive being shown not to work in the lab, they then went back to its ‘inventor’ who’d made a bigger one, and *surely* this one would work! When one of the astrophysicists they spoke to on the programme started laughing hysterically at some of these ideas, that should have been a clue to the programme makers!
I see the documentary is a “Horizon”. That should ensure that the quality is good.
Alex, that used to be a correct assumption but over the last 10 years or so ‘Horizon’ has gone downhill. There are far too many episodes that sway heavily to the sensationalist mindset and the show has suffered accordingly. The strange thing is that once in a while they do themselves proud and give us a really good episode, but most of the time lately I’m disappointed. Infact, Marc Millis was the one good thing about this ‘gravity’ episode.
You know my feelings on you and book writing Paul so I sant comment further as its your prerogative and what you have created in Centauri Drenas is indeed something special so I’m sure your very happy with your creation and deservedly so.
Gravity for me is THE key. The weakest of the four fundamental quantum forces yet unlike then able to exert influence over enormous distances and times as recently seen with gravity waves , rather than trapped in “quantum world “with most of the other forces .
Also THE great paradox that makes the two big theories of the Universe , big and very small , General relativity and quantum mechanics effectively mutually exclusive . One is wrong essentially as things stand as there is no quantum explanation for Gravity . Yet. Thanks to the Large Hadron collider we now have a Higgs boson which should explain mass. So will there ever be a “gravitron ” ? Now that would be a discovery . Maybe the very keystone of GUT, the “grand unified theory” or Holy Grail by which the two great theories are reconciled. Surely having found a gravitron you could then look to manipulate it and in doing so manipulate gravity, small scale first but finally on a large “General relativity ” scale . Spinning up hollowed out asteroid habitats in a pallid but effective impersonation of gravity suddenly looks very crude .
As a former physics grad student I have learned literally to -hate- Quantum Mechanics with a passion. Not because I don’t understand it but because from the very start, it cut off questions about the physical atom as irrelevant and naive. At least at the graduate school I attended.
Yes. And applying falsifiability and the increasing observational proof in favour of General relativity with gravity and such the like , where does that leave quantum mechanics ? Ahead of string theory in terms of having some observational proof via the LHC I suppose. As to GRT it’s hard to imagine its so old. Things from the past are meant to appear , well, old fashioned , yet it looks as clever and refreshingly new as ever. Timeless even though perhaps nothing could be further from the truth both literally and metaphorically.
Quantum mechanics is much more fundamental than regular physical theories. It is inevitable, even more so than General Relativity.
Discomfort with it is likely due to having been taught the wrong way. See this for a very enlightening introduction:
http://www.scottaaronson.com/democritus/lec9.html
Quote:
If you do not like quantum mechanics, Scott Aaronson just might open your eyes and turn you around.
I disagree. It’s a set of postulates on how to treat non-physical ‘wave functions’ assumed to exist which are solutions of the Shrodinger equation which itself was merely postulated. As a model it has severe limitations such as it cannot give accurate solutions to simple problems such as the states of the Helium atom without unwieldy approximation methods such as Hartree-Fock methods. Intuitively that suggests that the point model for the electron is the problem.
When I studied physics at university I was disappointed that QM has a tendency to turn unknowns into ‘laws’ thinking that solves the problem.
An example being ‘electrons in their orbits do not radiate’. Then they tell you don’t ask why just accept it as a law. That’s where QM failed me. It stops questions rather than leading one to ask better, deeper questions.
For that reason alone it should be treated as no more than a fair quality calculational tool that doesn’t get us to the truth. But we are bound by the ideas of a group of people from the 1920’s that no one questions. It’s time to question them.
I’m skeptical of your quote that one can ‘sprinkle in physics to taste’ to ‘calculate the spectrum of any atom you want’. Atomic spectra beyond simplified hydrogen take immense labor and the best methods are known not to be that accurate without making many assumptions. But feel free to show me I’m wrong. Perhaps you can show me how to calculate all the excited states of helium from scratch by hand with only paper, pencil and perhaps a calculator.
The standard model explains all the spectra of all the atoms, and has just a few parameters. Quantum mechanics explains how there can be spectra, at all. Why does it bother you that you cannot calculate the predictions with only paper, pencil and a calculator? What counts is that every single one, when you do calculate them, matches observations, perfectly.
I do not believe they match perfectly. If they did, why are chemists confined to using HF derived methods with arbitrary basis sets that only work with the addition of arbitrary parameters and thousands of functions. I’ve seen bogus calculations with an absurd level of significant digits, well beyond what the fundamental constants could allow, being touted as evidence but it seems they were curve fitting with an astronomical number of parameters.
Show me a simple formula, derived from first principles, using a handful of fundamental constants only and no arbitrary fitting parameters, that matches the excited states of Helium. I don’t believe you can. But you might show me a massive calculation contrived to fit each state separately after you know what the answer is. Then you will undoubtably claim that proves your theory is the best ever.
Clearly, the physicists are keeping the chemists in the dark!
I don’t literally require only simple hand calculations but having to use thousands of arbitrary basis functions seems unrealistic for a physical model even if it sort of works. It’s a kludge because you can’t solve a multi-body problem with a point electron model. In the Mills’ model, the electron is a two dimensional surface and the states are calculated as essentially a boundary value problem of the Maxwell equations for a perfect cavity. It’s conceptually very straightforward yet yields very good values for the states of multi-electron atoms (at least up to Z=20 so far) and excited states of hydrogen and helium (so far). It also predicts more stable states of hydrogen. It’s basically a classical atomic model and has been also developed into a general approach that allows molecules of almost arbitrary complexity to be modeled accurately. The software is freely available. What’s new and wouldn’t have been known in 1913 was a classical non-radiation condition that was developed by H. Haus at MIT decades later. Mills took a class with Haus at MIT which is where he learned of that non-radiation condition and applied it to the atom. If Mills is right and if the physics can be commercialized, we may ultimately get much of our energy from Mills’ discovery of more stable states and the conversion of hydrogen to them.
You seem to be confusing computational approximations with physical models. The simple formula you seek are the equations of the standard model, and they have very few parameters. The massive calculations you complain about are numerical methods to actually compute the spectra from the model. Those have no free parameters at all, but take a lot of ingenuity to come up with. And, as you say, they do not always look pretty. They are not, however, fitted to experimental data. When done right, that is.
People have been known to fit lots parameters to experiments, those tend to be people with pet theories different from the standard model. They get absurd results, like Mills. This is not really physics, though, it just looks like physics.
I suppose you assume that because the Standard Model can be expressed in a few neat equations that all the physics underneath is solved and it’s just slightly inconvenient that the computations are messy.
You say the HF computations have no free parameters at all but they have literally thousands of basis functions which were contrived to work. You can fit anything with thousands of basis functions.
Mills’ results aren’t absurd. They’re very real. He gets a lot of energy out of his supposedly ‘impossible’ reaction.
It is a pity that gravitational waves are so weak (metric ratios from waves generated by everyday accelerations and masses are 45 orders of magnitude smaller than unity), otherwise very interesting things could be done with them.
Yes, it is. One fact that is commonly overlooked is that we have already produced “designer gravitational fields”. In fact, we did it over 200 years ago. Remember the Cavendish experiment? Henry Cavendish measured the gravitational forces between two sets of lead balls in his laboratory. If we define gravity control as setting up a gravitational field with measurable effects, Cavendish did it! We create electromagnetic by moving charges around. Cavendish set up his own gravitational fields by moving masses around, and he succeeded in measuring them and determining the gravitational constant.
What’s more, you can control gravity in your own home too, if you are willing to take quite a bit of care setting up the experiment. All you need to do is bend spacetime in your basement.
We can manipulate gravity easily just by moving masses around. The problem is that the gravitational force is weaker than electromagnetism to the ratio of 4.17 x 10^42!! This is commonly overlooked by people who would like to control gravity.
The real problem is that darned equivalence of gravitational and inertial mass. That’s the killer. If you could vary them independently, it would be possible to have gravitationally powerful objects that could be moved around easily.
But they’re the same thing, so that will never be.
If my undergraduate days I was fortunate enough to have an excellent physics teacher who allowed us to actually do the Cavendish experiment.
If memory serves (mid 1970’s), we did it three ways and our error was surprisingly small! I was amazed that we could get close at all given all the issues like students walking down the halls and cars driving by. We may have done it on a Saturday.
I watched the show. I thought Marc Millis came across very well, but the programme pandered far too much to nonsense or fringe ideas – Eugene Podkletnov, EmDrive, even when it discussed dark energy it just focused on one scientist’s idea and ignored everything else. Science took a back seat to sensationalism with over the top narration from Peter Capaldi. Even though all these fringe ideas were shown to not work in the lab, the programme still felt like it was urging the audience to believe that they could work – “look, here’s a bigger version of the EmDrive, maybe it could work this time!” The general public watching this might come away thinking that we might just be a few years from anti-grav technology if only the scientific aristocracy would give these independent thinkers a chance.
Scepticism is a large part of the scientific method, about not being satisfied in your conclusions until you’ve exhausted all the other reasonable possibilities. While on the face of it the programme showed these ideas being tested and the scientific method being put into practice, the sense of scepticism was altogether missing, not to mention basic introductions to the science of gravity.
BBC Horizon used to be such a great programme, but I thought this episode was typical of its current faults and the way the media and the BBC treat science.
Thank you for that report, Keith. I understand a DVD will be mailed to me, but not sure how long before I see it.
PS – Did they include any of my discussion of inertial frames or the span of ongoing science relevant to gravitation?
I don’t recall anything about inertial frames – that would have involved talking about actual real science, which the programme tried its best to avoid. They showed you driving towards Glenn and you’re saying that NASA no longer does that kind of research; next you’re in a movie theatre showing a space shuttle launch and you’re discussing the huge amounts of fuel needed for conventional rocketry; and then they showed you riding up and down escalators with your voiceover talking about the results of your Breakthrough Propulsion Physics project.
No, the EM drive concept was not ‘shown not to work’. In fact all the data so far suggests it does work somewhat.
Breathless proclamations of antigravity and space drives are a favorite of the “alternative science” crowd, along with perpetual motion and supposed government conspiracies to hide the existence of both. I’m sorry to say that I suspect the BBC “Horizons” episode will bounce excitedly along the more entertaining crackpot schemes rather than give a measured look at “gravity control”. Many supposedly nonfiction and “educational” shows on the History and Science channel already run shows on ancient alien visitors and UFO lore, so the general quality of educational TV has fallen in general lately.
Researchers interested in these matters have their work cut out for them when it comes to explaining their work to the public. It is hard for laypersons to distinguish between work like the BPP project and stories of abused inventors inventing antigravity in their garage – which are often tied up in UFO lore to boot. There are two main varieties of antigravity device I have encountered. I will list them here for anyone who might run across them.
First off, mechanical antigravity devices are often encountered. These are actually attempts to make reactionless drives. Many involving cunning arrangements of oscillating weights in an attempt to trick inertia and result in an unbalanced net force on the vehicle. Others supposedly leverage carefully arranged systems of whirling gyroscopes. None of them have been shown to work, unless you count vibrating on a bathroom scale as sufficient proof to call for a departure from Newton’s laws. The BPPP already ran into trouble from this sector, see Marc Millis’s paper Responding to Mechanical Antigravity (2006).
One particularly famous example of a mechanical space drive is Norman L. Dean’s mythical “Dean drive”. John W. Campbell became interested in the device and ran an article on it in Astounding Science Fiction, claiming that if mainstream scientists were not so closed-minded to new possibilities (oh those terrible killjoy scientists!) we could have just mounted the Dean drive in a submarine to make an instant spaceship and gallivanted on a 1-g constant acceleration flight to Mars before Sputnik went up. Nothing came from it, as Dean refused to allow anyone to examine the device without being first given a large sum of money and a Nobel prize. Later on the patent was revealed to be nothing but a complicated ratchet crawling up a metal tape.
Even serious inventors have fallen into the “mechanical antigravity” trap. Eric Laithwaite, a British electrical engineer who contributed greatly to maglev trains, spent many years of his later life convinced that Newton’s laws could not account for the behavior of gyroscopes and that they could be used to make a reactionless space drive. He put forward his ideas when the Royal Institution invited him to give a lecture. The Royal Institute was not amused, and this was the only time in the history of the Institute that an invited lecture was not published. See Laithwaite’s Engineer Through the Looking Glass (1980) and 1975- A Space Odyssey Electrical Review, 28 March – 4 April 1975, pp. 398–400.
The next common class of antigravity drives are those based on supposed ties between electromagnetism and gravity. A large subclass are those based on the Bifeld-Brown effect. T. Townsend Brown was an American inventor who spent years convinced he discovered a connect between electricity and gravity after observing that a charged condenser has a tendency to move in the direction of the positive pole. The effect is real, but is actually attributed to an “ion wind” effect. Some people build “lifters” out of aluminum foil, wire, and balsa wood. When charged to a high voltage, they fly due to the ion wind effect noticed by Brown, but are incapable of producing thrust in a vacuum.
Nonetheless, proponents of “electrogravity” remain. They claim that just as a coil of wire is the link between electricity and magnetism, a charged condenser is the link between electricity and gravity. Others link Brown’s work to crackpot theories about the luminiferous ether. and another supposed electrogravitic device, John Searle’s “Ether Vortex Turbine”. Proponents claim that flying discs with ether vortex turbines have replicated the flight capabilities of UFOs, but the technology was suppressed by a government conspiracy. In a more bizarre turn, some people claim the B-52 Spirit stealth bomber actually has an antigravity mode based on ionizing the airplane’s exhaust!
Electrogravity is often tied in with ZPE “free energy” devices, perpetual motion, and aliens. I don’t know much about Nick Cook’s book The Hunt for the Zero Point, but I know his book appeared on the same shelves as books about electrogravity, perpetual motion, and UFOs. So I have very, very strong reservations about taking it too seriously. Perhaps it was put there just because zero point was in the title, but it was next to a book about something called the Michaelson-Morley device that supposedly produced free energy in the early 20th century from a charged plasma, but was suppressed by greedy industrialists. That was supposed to be zero-point energy too.
We must be careful, since ideas about breakthrough space drives can easily get lumped in with fringe mentality about antigravity. Furthermore, many discredited claims like cold fusion don’t die – they just find new life in the “Alternative Science” section of the bookstore. Many of these venues have already incorporated serious speculations about inertia and gravity control and worked them into these seductive fantasy worlds for adults. We can expect discredited ideas to linger on in the lunatic fringe, even after all serious scientists have moved on.
As an example, some people claim that the government has something called the TR-3B flying triangle. In contrast to the shiny electrogravitic discs of much UFO lore, this is a black triangle. The story goes that the craft neutralizes most of Earth’s gravity by using a rotating, super-dense fluid in a very large “gravity generator”. This story is clearly based on the ideas outlined Robert Forward’s paper Guidelines to Antigravity (1962). People are quite willing to incorporate anything with the word “antigravity” attached to it into UFO lore. Unfortunately, this will make it harder for physicists interested in breakthrough propulsion to separate their research from the lunatic fringe in the public’s mind.
In the ‘Frontiers of Propulsion Science’ book there is an updated version of ‘responding to mechanical antigravity’ paper, covering Dean drive concepts and Laithwaite’s misconception of angular momentum… plus what a fan would need to do to prove it’s real (raise the bar on rigor). We also have two chapters devoted to the “lifters,” both of which independently came to the same conclusion of induced air currents. And – there is a chapter on making sure not to mix conventions of representing photo momentum in media – where others (when mixing those conventions) conclude there could be a thrusting effect.
With all the hype of the fringe stuff, and then occasional professionals not working up to normal standards of rigor, it’s hard to bring the more substantive (yet less exciting, slower paced) work to light.
In regard to alternative propulsion methods, I was in the Navy, back in the long ago, so naturally when the caterpillar drive described in ‘The Hunt For Red October’ (loosely based on Bernouilli’s prinicple) showed up, I asked a retired nuke pigboat friend of mine if it would work.
Was it actually feasible to develop and use it? His response, because his job required skilled knowledge of such things, was blunt: It seems like a good idea on paper, but no, it does not work.
Do you mean the MHD drive? The kind where a boat doesn’t have any moving parts, but instead runs electrical current through the water in the presence of a magnetic field to push the water out the back of the thruster with Loretnz force? As I understand, the concept is elegant and futuristic, but not practical – at least for now.
It does work, however. A prototype sub was built using an MHD thruster, and in Japan a prototype boat called Yamato 1 was launched that tooled around Kobe harbor using two MHD thrusters. However, such thrusters produce gasses, noise, and a noticeable magnetic signature that would make them quite hopeless as a “stealth” drive. In the novel, the propulsion system was a pumpjet.
MHD thrusters could also be used in space propulsion. However, they are simply another kind of rocket once you have to carry your own propellant.
I don’t know how Bernouilli’s principle applies to MHD drives, though, so perhaps you mean the pumpjet instead? I never bothered to wonder how practical that was because it sounded so boring! *laughs* But pumpjets do work, was he talking about their stealth characteristics?
I very much want to read Frontiers of Propulsion Science, and now that you tell me that it covers these common fringe science ideas I definitely must add the book to my collection! I’ve always had an interest in alternatives to rocket propulsion, so I’ve been aware of mechanical antigravity and lifters since childhood. It’s important to clear the air of stuff like this so we can get on with the research that might actually result in something.
I very much like your attitude of not dismissing questionable science offhand, but instead forming your judgement based on how serious and rigorous the researcher is. The real problem with people like Norman L. Dean is not that they peddled a device that doesn’t work, but that they refused to rigorously test the device to prove it is real. This was, of course, because it was a scam. But if someone rigorously and impartially tests all their claims, it doesn’t matter much even if they are wrong. They will soon find out if their device is worth anything or not, and they have a much better chance of discovering something useful. And even negative results are useful.
The really important, rigorous test for a reactionless drive is of course the pendulum test. Hang the device from a cord of some kind and turn it on. If you can get it to hang non-vertically, get interested. Cover it with a garbage bag and try it again. If it still hangs non-vertically, get really interested. Then it is time to call up your local university’s physics department and see if they can find anything wrong with your setup- like stray magnetic fields or some other factor that accounts for the anomalous thrust. Oh, and patent it and get rich. *big grin* The ultimate test will be launching it into space and using it to change the orbit of a satellite. Oh, and have fun watching the physicists sweat while they tear apart the whole structure of modern physics to account for your device. *laughs* Sadly all the above is most probably going to remain a fantasy.
Yes, the fringe stuff attracts much more attention than the more substantial research. Still, we must keep trying to debunk those ideas that never did work and bring the serious research to light. You can research exotic propulsion with the same standard of rigor as any other field of research. It’s important (for students especially) to make that clear. You aren’t a crank if you research the physics that might allow an advanced civilization to use wormholes for interstellar travel. You are a crank if you refuse to hold your work to an acceptable level of rigor.
As long as were talking about things way out there…..
What we need is the propulsion system invented by Frank Herbert in Dune. It would be very useful to be able to ‘fold space’ with our minds.
Alas, the closest I can envision would be lucid dreaming or out-of-body experiences where the experience at least seems real and one can explore other worlds even though they really only exist in one’s mind. Kind of like one’s own personal holodeck.
Guild navigators were folding space in their minds as mathematicians, ‘thinking’ machines having been outlawed. Their psychic abilities were to foresee whether all this space was empty beforehand.
The link to the BBC is here:
http://www.bbc.co.uk/iplayer/episode/b0752f85/horizon-20152016-2-project-greenglow-the-quest-for-gravity-control
You will need a VPN pointed at a UK IP address to view it.
Thanks!
Hi Marc,
I haven’t been able to view the episode as it seems to block the video for outside UK viewers, no doubt it would have been very interesting to watch. As far as GCP (Gravity Control Propulsion) is concerned, I came to the following conclusions so far (I stand to be corrected):
– None of the proposed physics models/experiments conducted to date have shown that GCP can be a possibility ie in 2016 it is still an unviable concept.
– General Relativity alone cannot answer if GCP is viable.
– Without GCP, I severely doubt we’ll be able to build large starships in the foreseeable future, ie this is a make or break issue to allow us to start large scale space exploration.
– More info in this paper for anyone interested:
http://vixra.org/abs/1506.0194
Cheers, Paul.
Here it’s a very interesting possibility to control the gravity I wonder why there’s not private companies interested in test it:
http://www.ibtimes.co.uk/gravity-major-step-physics-mathematician-unveils-formula-creating-gravitational-fields-1537182
How Current Loops and Solenoids Curve Space-time
http://arxiv.org/pdf/1504.00333v3.pdf
Light should not be affected by magnetic fields, superposition principle, a LIGO setup in space should be able to determine with great accuracy any effect of the magnetic field upon light. If there is then photons possibility will have a direct relationship with gravitons, maybe gravitons are extremely long wave photons.
I want my hour back. Peter Capaldi (Dr. Who) breathlessly takes us on a tour of some science and crackpottery. The documentary even dismisses the EmDrive after -ve experiments, but ressurrects it as working near the end in Shawyer’s hands.
Gravity detection is conflated with gravity control, as well as invoking dark energy, anti-matter and negative matter as potential anti-gravity.
I’m reminded of an engineering friend of mine who was taken by the idea of unbalanced spinning masses to make a reactionless drive. He would say “I know it doesn’t work, but what if it did?”, and then make another experimental rig that he convinced himself was doing something but obviously didn’t, and wouldn’t accept advice on how to do better tests This is what Marc Millis is saying about rigor.
And that sums up this documentary. It was all speculation, a parade of ideas that failed to work under rigorous conditions, but then miraculously worked under different, non-rigorous conditions.
Very unsatisfying. I felt like it was constantly holding out a carrot then pulling it away, only to offer a different carrot. At the end, I felt like Charlie Brown being fooled by Lucy holding the football for the umpteenth time.
Why are you looking for science in entertainment?
These discussions are always fascinating. IMO nobody does it better than John Cramer. Here’s one of my favorites: http://www.npl.washington.edu/AV/altvw162.html Unfortunately there is always the fine print such as: “let us assume we can snatch microscopic wormholes from the quantum foam and stabilize them.” In other words, if pigs had wings they could fly. But to continue this analogy, genetic engineers might create aerodynamic pigs with wings someday. And maybe we can figure out how to create and stabilize a wormhole. After all, this website is named Centauri DREAMS, not Centauri Project, Centauri Mission, etc.
Another example along the lines of “if pigs had wings” thinking: If we could control dark energy, we could probably use it to control gravity, given that dark energy’s repulsive force seems to counteract gravity.
The documentary can also be downloaded from this BitTorrent file with a suitable client.
BBC Horizon 2016 Project Greenglow The Quest for Gravity Control
If it weren’t for this site, I would not be able to come up with some of the crackpot ideas I have for science fiction. It’s much better than high school, and certainly better than college because I don’t have to have math skills (eeeek!!) to understand the context or the ideas.
What I have not yet found an answer to anywhere at all is a few simple questions:
A – Is gravity the product of mass + volume, or is it something else? (I always got blank looks for that one.)
B – If one of the four basic forces of physics (strong, weak, electromagnetic, gravity) is permanently disrupted, how does that affect the others? Or does it affect them?
Science fiction is ideas, a way of exploring possibilities, but when someone says ‘can’t be done’ or ‘doesn’t happen’ , that shuts the door in the face of exploration and innovation. I can’t get BBC TV, so I was spared the necessity of watching any crackpot ideas and conspiracies being flouted.
However, heavier-than-air flight was once considered to be a crackpot idea, wasn’t it?
This is why I love this site and am happy to have found it. And NO MATH REQUIRED!!!!
Hi Sara, Personally I like MOND (Modified Newtonian Dynamics) https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics. The attempts to find dark matter so far have resulted in nothing but negative results. I suspect dark matter is like the “ether” Michelson and Morley were looking for in their famous experiment. Although MOND has its flaws, dark matter has even bigger flaws because it has never been detected.
A: Gravity results from mass. It’s effect spreads over space (volume).
B: Not sure exactly what you are asking, so I’ll guess. Q: If the fundamental forces are interconnected, does affecting one then affect another? A: Yes, in principle. On an easier example, electric fields and magnetic fields are interrelated in a way where we can manipulate electric fields to create magnetic fields and vise-versa. When it comes to the fundamental forces, the details of how far one can push that analogy get confusing. And General relativity suggests that ANY form of energy, if really intense, can warp spacetime, and warped spacetime is another way of describing gravitational effects. Oh the challenge of conveying this, when each statement can branch off into various themes and caveats.
In Newtonian mechanics, gravity is understood to be the force between two masses. What Newton said was that every particle on the universe attracts every other particle with a force directly proportional to the products of the two masses and inversely proportional to the square of the distance between them. In Mathese:
F = G* (m1*m2)/(r^2)
where F is force, G is the gravitational constant (6.674×10?11 N?·?(m/kg)^2, don’t ask), m1 is the first mass, m2 is the second mass, and r is the distance between the centers of the two masses
In plain English this means that that the force of gravity between any two masses depends only how big the masses are and the distance between them. Volume has nothing to do with it. Any high school physics book can teach you this easily with nothing but some basic algebra skills, so don’t be afraid.
Regarding question B, I’m not sure what you mean by “permanently disrupted”. So far as we know the four basic forces work they way they work and we cannot disrupt or change any of the laws of physics. We can, however, imagine hypothetical universes in which the laws of physics were not the same. We can imagine that the gravitational constant has a different value, making gravity a stronger or weaker force. Or we can modify one of the other constants and make the weak nuclear force work differently etc. Such thought experiments are played out in mathematical toy universes. Usually we find that even a tiny change to one of the four fundamental forces makes life impossible. If gravity were stronger, all stars might collapse into black holes. Or a slight change to the weak nuclear force might mean that there is no carbon for making our kind of life. This observation as lead to the Anthropic Principle, in both its strong and weak variants.
It’s really impossible to discuss these ideas in a meaningful way without math, however. Math is just a language for stating certain ideas in a quantitative way. English is very imprecise and clumsy for dealing with anything involving quantity or measurement, which is why physicists use math. So you are not going to get much of a better answer to the above questions anywhere if you are that allergic to math. Question B, in particular, is played out only in toy mathematical universes.
Regarding crackpot ideas, heavier-than-air flight was only ever considered a technological problem. Birds had been doing it for millions of years before the Wright brothers. And scientists who made pronouncements to the effect that flying machines were an impossibility were unwarranted. However, they were making such pronouncements about things that were not basically physically impossible. If they made similar pronouncements regarding Cavorite from H.G. Well’s The First Men in the Moon, they would be exactly right. Gravity does not work that way, and the Cavorite would violate the laws of thermodynamics.
I suspect that many pronouncements made today about the infeasibility of certain technologies – like generation ships, antimatter, mass collection of solar energy, etc. – will prove to be as wrong as the earlier ones about flying machines and rockets. However I think that the negative pronouncements have a much greater probability to be right regarding devices that contravene basic laws of physics. Breakthroughs are possible, but later discoveries in physics will fit in with what we already observe about the universe.
NASA is a space agency isn’t it? Space is unimaginably vast; yet to my knowledge NASA doesn’t devote any resources to substantially increasing the speed at which we travel in space to cut down on travel time or at least let us get to the next solar system in a human life time (or even travel cut down transit time in our own solar system). NASA has a $19 billion a year agency that in my opinion should devote to spending 1% of annual budget on FTL and sub-light propulsion.
Rumour has it that a Shawyer EmDrive flew on the USAF X37-B spaceplane. Our tax dollars at work – that is, if they share the results with us taxpayers.
And rumor also has it that the B-52 Spirit has an antigravity mode based on charging the plane’s exhaust to harness the fictitious “electrogravity”. And a whole bunch of people are still convinced that mechanical antigravity devices work. The fact is that discredited ideas don’t die – they just go on to a new life in a complex fantasy world some adults choose to live in. Emdrive will be with us for decades to come, as T. Townsend Brown’s “gravitator” has whole books devoted to it in fringe bookstores. Along with chapters devoted to the Dean drive and Laithewaite’s confusion over gyroscopes.
I’m pretty sure the signal has been out of the noise for some time, perhaps 3 years?
The thrust levels reported so far are in the micronewtons, uN. Millinewton (mN) thrust levels are required. Newton levels are highly desirable.
Now, one needs to distinguish physics, engineering and aerospace. In order to meet aerospace requirements, the physics folks need to produce suitable results for the engineers to meet the aerospace requirement of Newtons per kilowatt (electrical), N/kWe. At least 2 N/kWe is required for engines in horizontal flight and 20 N/kWe for vertical flight.
The Anonymox Firefox plugin allows BBC streaming to other overseas locations.
Just putting it out there: There could well be a close connection between gravitational (not gravitation) waves and dark matter. Energy stored within gravitational waves is difficult to detect and has little interaction with ordinary matter (only affects the space between particles of ordinary matter). However the energy within gravitational waves would have a mass equivalence that would warp space-time similarly to ordinary matter. I’m just saying…
I looked into the m-drive a few months ago. In the well accepted theory of wave-particle duality, ‘wave-packet’ velocity is regarded as velocity of the equivalent ‘particle.’ Detailed analysis of the em-drive frustum does indicate that the velocity of microwave wave packets reflected at one end of the device is greater than at the other. This supports the contention that the momentum transferred to one end is greater than the other. This does seem to challenge our concept of the conservation of momentum, however one can examine the situation from special relativity principles then we can consider that the microwave is in its own inertial frame (or whatever the ‘inertial frame’ is for a wavicle traveling at c), quite separate from the inertial frame of the frustum’s reflecting walls. In relativity, human conceptions of time, velocity, and the simultaneity of events break down when reference frame of the observer changes. Perhaps the microwave’s momentum is conserved in its own frame, but does not appear to be in the frame of the device? The relativistic universe is God’s elastic acre, where seemingly immutable quantities stretch to keep the universe whole. Possibly under observation our concept of momentum will also becomes less rigid?
By ‘wave-packet’ velocity I meant to say the ‘group velocity’ of the microwave quanta.
2014 study of group velocity contends photons travel in free space slower than the speed of light due to transverse geometric factors (e.g. wave guides):
http://arxiv.org/abs/1411.3987
From the paper: “One sentence summary: The group velocity of light in free space is reduced by controlling the transverse spatial structure of the light beam.”
Read carefully. Photons are not travelling less than c. The devil is in the details, as fully described in the body of the paper.
To be more precise, the light wave travels at c, however the group velocity – which is the photon particle – travels more slowly when the transverse structure of the ‘beam’ changes.
It is a common understanding that velocity associated with the momentum of a particle of matter (mv) is the group velocity of the corresponding matter wave.
Photons traveling at c are a special case where momentum is a function of the wave frequency. However, photon particles — or group velocity — which travel less than c in a vacuum are also a special case.
“the group velocity – which is the photon particle”
That is not the definition of group velocity. Not even close.
https://en.wikipedia.org/wiki/Matter_wave#Group_velocity
I am making an argument analogy between De Broglie theory as it relates to matter wave/particles (and their momentum( and the special case of a light wave propagating through a wave guide with a group velocity less than c.
Is it a solid analogy? I don’t know. Those better trained in the ways of science would have to weigh in. But with my limited training I feel there is something to this analogy that could help explain an em-drive theory of operation.
I’m happy for anyone to explain their point of view in greater detail.
Meant to write “…the group wave packet – which is the photon particle…
We have here a superposition of microwaves, propagating in roughly opposite directions within the wave guide, and reflecting off each end.
Each ‘group’ of ‘waves’ is a ‘bulge’ in the probability wave of of the presence of any number of photon quanta.
But since we have a standing wave (or as close as we can get to one), we would not expect to see the blips move.
But lab analysis of the em-drive shows that the blips of photon presence have a higher group velocity on one end of the wave guide than the other.
It is group velocity that conveys momentum and information in a matter wave
For a light waves moving at c, I have read that the light wave superposition can convey information at the speed of its group velocity, which cannot be greater than c if the photon is ‘bound.’
I don’t know if science has learned that a microwave similarly conveys momentum with group velocity. This could be something new?
It is perplexing and interesting.
I’m shocked to hear that I’m not the only one on Earth who remembers editor John W. Campbell pushing the Dean Drive (and the possibility of a 4th law of motion) as the answer to our space travel problems. Yes, I remember the cover of an issue of ANALOG (or perhaps one of the last issues of ASTOUNDING as the title was being changed to ANALOG) with a submarine fitted with a Dean Drive on the way to Mars. And this was supposed to be THE hard science SF magazine? I’m speechless with nostalgia for the golden days of my youth — and also blushing. Please don’t get me started on Hieronymous machines and psionics!
Hey, I remember! As a schoolboy in 1962, I even ordered and received a copy of the Dean patent! Yes, I figured out that it was a lot of hooey; the thing just sort of ratcheted itself along a rod or rack. Those were the days!
A lot of hooey for space travel, yes, but there are potential applications for using inertia to move when a track or road is available. My dad made a toy train powered by whirling weights. Perhaps it could replace both the drive train and brakes of a car.
I don’t think so, because it still basically works by friction against the track or road, so just having wheels that are turned by the motor in the usual way is more practical. The inertia really won’t get you anywhere.
I think your right about that…
Really? Those were indeed the days! I use to thumb through books with titles like “The Anti-Gravity Handbook” that collected patents for crankish devices, bizarre speculation, and conspiracy theories in one place. All those mechanical antigravity devices and Bifeld-Brown “lifter” devices were discussed in those books. Along with the space aliens we supposedly stole the ideas from. I too figured out it was all hooey. :^D
http://backreaction.blogspot.com.au/2016/03/researchers-propose-experiment-to.html
Interesting experiments coming soon.
Marc,
Physics studies the experience of the Universe.
This approach is called a Black Box approach —— where we choose to ignore the content of the Black Box and work only with inputs and outputs.
NOW would be a good Time to start figuring out what is in this Black Box!
If we don’t, if we choose to ignore it, we have NO chance at controlling GRAVITY. In other words, until we understand the content of the box (substance and cause) we don’t have a clue about what we are really doing.
The ultimate purpose of science is to understand the “Nature” of the Universe i.e. what it is by itself, not the way we experience it. The trap here, is to believe that we know something, when we actually don’t.
Marcel,
This is a perfect example of an utterly meaningless pseudo-idea. It is completely untrue to say “The ultimate purpose of science is to understand the “Nature” of the Universe i.e. what it is by itself.” There is no question of understanding what anything (let alone the Universe) is “by itself” or “in itself”, because that doesn’t mean anything. The only content of knowledge is structure, as Korzybski so wisely said. I think you may be alluding to Kant or Hegel’s “Ding an sich”, but that concept has long been exploded.
You said “… until we understand the content of the box (substance and cause) we don’t have a clue…” We can never understand the content of the box in the way you are trying to suggest; actually the very idea is empty of meaning. And “substance” is a vaguely religious concept with which science has been at open war for quite some time.
Thomas,
I’m afraid you are wrong. We were all wrong and arrogant in believing otherwise. We lost a good 100 year because of it. The difference between “experience” and “substance” is enormous, not only in quantity but also in knowledge. This difference has already been calculated; I give you dark matter and dark energy. Your own calculations! You don’t believe or understand yourself? The content of the box is simple and works by logic.
There being only one substance, we never had to wonder what it was. Working by logical operations made mathematics unreasonably effective.
But in the end, tackling gravity’s fundamentals requires that we put our nose in the box.
Here is a citation for you:
“Science doesn’t make a move until philosophy allows it and encourages it to do so.”
? Thomas Mann
Now is the moment
Marcel,
Your post doesn’t seem to me to make any sense at all.
Thomas Mann was a fool. Science leads philosophy, not the other way around.
Thomas,
Don’t get me wrong. I am really trying to capture something out of this exchange. What “we miss” by using the black box approach was simple to understand, but you did not get pass that. I will meet other people like you and I have to understand the hurdle I am facing. Is this because of a blockage of sort or is this educational damage?
Bottom line, Thomas: All you really had to do, was ask: “Marcel, what is in the box”? I invite you to reflect on the real reasons why you did not ask the question.
Marcel,
At this point we need to get back on topic — in the case of Marc’s post, the topic was the need for impartiality especially as it applies to the media on the subject of the scientific study of gravity. We are now getting into issues of philosophy and even psychiatry — this is the wrong site for this. The comments policy appears on the front page for reference.
Sorry, Paul, Thomas. I will comment on the actual topic.
OK! This is 2016, and we still send good men and women in space sitting on huge amount of explosives… Gravity control? Not yet! We may safely say that apart from the categories of the delusional crackpots and pedantic prudes, all other categories had a chance, and failed.
My point is this. Our approach didn’t work (Marc Millis included). Repeating it, means we haven’t learned anything. We put in place peer review and other types sieves that sort out ideas that are not our own. This is not the way to explore new ideas. We are 6 billions … Crowd sourcing should be for new ideas.
For those who are still curious and open to new ideas, I have a poster presentation 5-9 June 2016 Cambridge Mass. at the Science of Time Conference. Link to my abstract: http://sot2016.cfa.harvard.edu/SoT2016/cgi-bin/TXT/Poster/Oral_LeBelMarcelMarie.txt_N.html
Good luck,
Marcel,
Once impartiality and rigor qualify the ideas and experiments of either author or speaker, the next major step towards the stars is the vetting process. Millis has at least two that are useful: the 2004 Mapping of Physics to Breakthrough Propulsion goals which appears in part in the 2009 Davis/Millis book Frontiers of Propulsion Science, and a vetted summary in a 2014 presentation on Frames of reference
http://aspw.jpl.nasa.gov/files/ASPW2014%20PRESENTATIONS/WEDNESDAY/Breakthrough%20Prop/Millis.pdf