by Paul Gilster | Feb 13, 2006 | Breakthrough Propulsion |
In a paper to be delivered tomorrow at the Space Technology & Applications International Forum (STAIF) in Albuquerque, Franklin Felber of Starmark Inc. (San Diego) will present research on the gravitational field of a mass moving close to the speed of light. Without seeing Felber’s work, Centauri Dreams is reluctant to comment on his assertion in an article on the Physorg.com site that “…a mission to accelerate a massive payload to a ‘good fraction of light speed’ will be launched before the end of this century…”, other than to say that STAIF is a venue where fascinating ideas routinely emerge, not all of which stand up to scrutiny.
The paper is titled “Exact Relativistic ‘Antigravity’ Propulsion,” and it is followed by another intriguing title, “The Alcubierre Warp Drive in Higher Dimensional Spacetime,” by Eric Davis and H.G. White. Also worthy of attention is James Woodward’s “Mach’s Principle, Flux Capacitors, and Propulsion.” More on all three as information becomes available. You can find the entire STAIF schedule here.
by Paul Gilster | Jan 10, 2006 | Breakthrough Propulsion |
Centauri Dreams asked Marc Millis, former head of NASA’s Breakthrough Propulsion Physics Project, for his thoughts on so-called hyperspace propulsion, as recently published in an article called “Take a Leap into Hyperspace” (New Scientist, 5 January 2006). The article has received wide coverage because of its sensational implication that we may be much closer to a breakthrough in interstellar propulsion than anyone realized. And as discussed here in the last few days, it draws on the work of the German theoretician Burkhard Heim and the later refinements of Walter Dröscher and Jochem Häuser.
Millis’ response follows. But he leads it off with this qualification: “My assessments below are only a cursory response rather than the result of a full technical review. If I had done a full technical review, I would have submitted it to a journal. Given the level of interest, however, and the habit that many of us have to jump to conclusions (pro or con), I thought I should comment.”
With that necessary provisio, the podium belongs to Marc Millis:
First, there are many different approaches in the literature related to breakthrough propulsion, not just this one. Each is at a very early stage of inquiry. As much as we’d like the final answer NOW if any of these will lead to a real interstellar craft, that question cannot yet be reliably answered. Instead, we should be asking: “What do we work on next; what is the next step?” This is the context in which I’ve framed my comments.
On this particular approach, where Dröscher and Häuser build on the theories of Heim to suggest propulsive effects, the next logical step is to verify the assertion that the Heim theory correctly predicts the masses of subatomic particles; this assessment should be carried out in the open peer-reviewed literature so that the results and its verification are traceable (instead of by anecdote). A confirmation of this assertion, by itself, would be significant. Since this task only requires analysis, instead of experiment, this should not be too costly for the advocates to support themselves.
For those advocating the Heim theory, it would also be very useful to have a more tutorial version of Heim’s derivations (and in English) to help the greater community understand precisely what is being done. From the German 1977 paper and other text I read, I only found the assertions without the step-by-step explanations for how these were developed. The existing publications are insufficient to convey the theory.
Also, it should not be forgotten that the Heim theory and its propulsive implications are two separate issues. It seems that Dröscher and Häuser reintroduced dimensions into the Heim theory that Heim had dismissed, so even if the mass prediction claims of Heim are confirmed, there is no guarantee that the modified theory would, itself, be valid. Having this conversion step explained, and in the form of a peer-reviewed paper, would be quite helpful. As it is, I could not follow the details myself in my quick scans of the papers.
Regarding experimental tests: As much as I am a strong advocate for experimental tests, there is the issue of relative cost. Again, there are other options out there that might be worthy of support. With the Dröscher-Häuser experiments, I could not tell if their experiment was the least-expensive approach to validate (or falsify) their theory. When competing with lesser-cost options, this will be an issue. I strongly recommend that any experimental proposal be designed to be the lowest-cost experiment sufficient to clearly falsify or support the theory.
And this brings me back to the issue of the other options and research funding. Although I still track such developments in my discretionary time, the NASA Breakthrough Propulsion Physics Project is no longer funded and I know of no other group within NASA that is authorized, qualified, and funded to support such on-the-edge propulsion physics. There are pockets of activity scattered across government, industry, and academia, but these are typically small discretionary efforts. If it turns out that there are any funding sources interested in such breakthroughs, I’d recommend having a competitive research solicitation to help identify the best prospects.
For those who do not already know, I recently published overviews of the approaches that I know about, including the work that NASA and others supported. But even these papers do not encompass all the possibilities. I also published a paper on the management methods for dealing with such visionary and provocative prospects in a constructive manner, including the criteria for competitive solicitations. I hope you find these useful:
(1) Summary of options:
Marc G. Millis, Prospects for Breakthrough Propulsion From Physics, NASA TM-2004-213082 (2004 May)
(2) Management methods:
Marc G. Millis, Breakthrough Propulsion Physics Project: Project Management Methods, NASA TM-2004-213406 (2004 Dec.)
(3) Options, methods, and estimating benefits:
Marc G. Millis, “Assessing Potential Propulsion Breakthroughs”, Annals of the New York Academy of Sciences, (due out early 2006).
In closing:
This Dröscher-Häuser-Heim approach is in such an early stage of development that it is premature to judge its viability. Fortunately, relatively low-cost next-steps could be taken by its proponents to help others assess the prospects, such as confirming (in the open literature) the ability of the Heim theory to predict the masses of subatomic particles, and showing the derivations and equations necessary to comprehend the other assertions.
Also, it is important to remember that there are many other approaches out there. The best way to determine which of these might merit support is to conduct a competitive research solicitation. There is no NASA funding planned for such an assessment in the foreseeable future.
Centauri Dreams note: Those who continue to follow developments in deep space propulsion will already be familiar with the Breakthrough Propulsion Physics Project. BPP looked at such controversial topics as gravity control, space drives, faster-than-light travel, and vacuum energy, and did so in a credible and efficient manner. For a total investment of only $1.6M spread over 1995 to 2002, this project produced 14 peer-reviewed journal articles, addressed 8 different research approaches, posted an award winning Web site called Warp Drive When, and garnered over 100 positive press articles for NASA.
Since funding for BPP was deferred in 2003, Millis has been actively pursuing the creation of a foundation that can serve as an alternate venue to continue and enhance research and public education toward practical interstellar flight. Centauri Dreams will have more on this work as it develops. For now, background information on the foundation (including a document outlining its charter) may be found here.
by Paul Gilster | Jan 7, 2006 | Breakthrough Propulsion, Culture and Society |
With hyperspace suddenly in the news, here are some thoughts on how taking a shortcut to reach the stars has appeared in science fiction. They’re from The Science in Science Fiction, edited by Peter Nicholls (London: Book Club Associates, 1982), p. 72:
“Hyperspace is the science fictional name for the ‘other space’ used in such short cuts. The word was invented by John W. Campbell for his short story “The Mightiest Machine” (1934) and unashamedly stolen by hundreds of writers since. Today, hyperspace is part of science fiction’s standard furniture — solving all those awkward problems of travel to the stars…
“[One] view of hyperspace is as a ‘universe next door’ much smaller than our own, with every point in hyperspace corresponding to one in this universe. Mathematicians call this a ‘one-to-one’ mapping. So hyperspace behaves like a little map of our own universe, a map which can be visited — as though we could step from London to the point marked ‘London’ on the map, walk a short distance to the point marked ‘New York’, and step out of the map into the real New York. Again, the difficulty is getting into the map — into hyperspace — in the first place.
“This model features in Frederick Pohl’s story “The Mapmakers,” in which (logically enough) an error in positioning of 1 cm on the ‘map’ can bring a ship back to normal space millions of light-years from its planned destination. There is no reason why hyperspace travel should be even this simple. In Bob Shaw’s Night Walk the hyperspace universe has a fiendishly complicated shape, like a mathematician’s nightmare — the odds are that inexperienced travellers will end up at completely random points in our space, and will never get home again.
“Still more depressing is George R.R. Martin’s story ‘FTA,’ where people break into hyperspace and find that it is not a short cut after all. Why, apart from wishful thinking, should it be? In this story, to go via hyperspace takes longer.”
Centauri Dreams‘ take: There’s nothing wrong with being an optimist, and while the Martin story makes for good reading, a determined effort to push the limits of the possible may one day pay off in a true superluminal breakthrough. But the key to this kind of research is to understand that it is incremental, that progress is likely to occur in a series of small steps that build the foundation for the great events that follow, and that this incremental work should be an ongoing process. Everybody hopes for the grand design discovered in a scientist’s papers, one that will turn everything over in the blink of an eye, but getting to the stars is more likely to be a matter of slow, patient physics that keeps probing the nature of spacetime even when the news media have moved on to other topics.
by Paul Gilster | Jan 6, 2006 | Breakthrough Propulsion |
A story in The Scotsman discussing how a hyperspace drive might work is in wide circulation, and today I read the feature in New Scientist that it’s based on (thanks to Ian Brown for the tip). Under discussion is the possibility of building what is being called a ‘hyperspace engine,’ one that could get us to Mars in a matter of hours and to the stars within the kind of time frames once demanded of the crews of sailing ships. But to say that the theories behind this drive are controversial is to turn understatement into a virtual art form. Here’s what The Scotsman has to say about how such an engine would work:
The theoretical engine works by creating an intense magnetic field that, according to ideas first developed by the late scientist Burkhard Heim in the 1950s, would produce a gravitational field and result in thrust for a spacecraft.
Also, if a large enough magnetic field was created, the craft would slip into a different dimension, where the speed of light is faster, allowing incredible speeds to be reached. Switching off the magnetic field would result in the engine reappearing in our current dimension.
Heim is obscure by choice; a rocketry enthusiast who suffered massive injuries in a laboratory experiment during the Second World War, the German scientist shunned publicity and died in 2001 largely unknown, the author of only a single peer-reviewed paper. His work grew out of his attempt to bridge Einstein’s general theory of relativity and the startling world of quantum mechanics. Heim’s revised equations of general relativity resulted in a six-dimensional universe that addded a two-dimensional ‘sub-space’ onto Einsteinian spacetime. Out of his logic came the idea that electromagnetic energy can be converted into gravitational energy and vice versa. Although Heim failed to follow up on hyperspace propulsion possibilities, Walter Dröscher extended his work to include more dimensions and two new forces, one of which might drive a spacecraft.
Joachem Häuser (Applied Sciences University in Salzgitter, and former chief of aerodynamics at the European Space Agency) worked with Dröscher to produce a paper on space propulsion using Heim’s ideas that won an award from the American Institute of Aeronautics and Astronautics last year. Both he and Dröscher believe it is possible to put Heim’s ideas to the test. Here’s how New Scientist describes the experiment that the two would use:
This will require a huge rotating ring placed above a superconducting coil to create an intense magnetic field. With a large enough current in the coil, and a large enough magnetic field, Dröscher claims the electromagnetic force can reduce the gravitational pull on the ring to the point where it floats free. Dröscher and Häuser say that to completely counter Earth’s pull on a 150-tonne spacecraft a magnetic field of around 25 tesla would be needed. While that’s 500,000 times the strength of Earth’s magnetic field, pulsed magnets briefly reach field strengths up to 80 tesla. And Dröscher and Häuser go further. With a faster-spinning ring and an even stronger magnetic field, gravitophotons would interact with conventional gravity to produce a repulsive anti-gravity force, they suggest.
Häuser notes that the basic science of the hyperspace engine, still unproven, would demand a change in our understanding of the laws of physics, but he does believe that it would be possible to test a working device within five years. The upside: the kind of drive Häuser describes could get us to Epsilon Eridani (about 10.7 light years away) in 80 days, which is reason enough to hope the basic concepts can be verified. The downside: the basic science behind Heim’s work is obscure and has only recently risen to the level of serious investigation. That investigation will doubtless tell us whether the effects forecast by Heim really do offer us a gateway to the stars, but unravelling the scientist’s work is going to be a lengthy process. Markus Pössel, a theoretical physicist at the Max Planck Institute for Gravitational Physics in Potsdam, isn’t the only scientist who finds Heim’s work ‘largely incomprehensible,’ but see the New Scientist article for other reactions.
You can download papers by Drs. Dröscher and Häuser, including the award-winning paper “Guidelines for a Space Propulsion Device Based on Heim’s Quantum Theory” here and also at the HPCC-Space GmbH site. Centauri Dreams thanks Dr. Berkant Göksel (Technical University, Berlin) for sending these links last year, and for passing along the original news of Häuser and Dröscher’s AIAA award.
by Paul Gilster | Dec 31, 2005 | Breakthrough Propulsion |
Centauri Dreams recently examined wormholes and their possible survival from the early universe through the mechanism of a negative mass cosmic string. But what exactly is a cosmic string? Here’s Lawrence Krauss on the subject:
“During a phase transition in materials — as when water boils, say, or freezes, the configuration of the material’s constituent particles changes. When water freezes, it forms a crystalline structure. As crystals aligned in various distances grow, they can meet to form random lines, which create the patterns that looks so pretty on a window in the winter. During a phase transition in the early universe, the configuration of matter, radiation, and empty space (which, I remind you, can carry energy) changes, too. Sometimes during these transitions, various regions of the universe relax into different configurations. As these configurations grow, they too can eventually meet — sometimes at a point, and sometimes along a line, marking a boundary between the regions. Energy becomes trapped in this boundary line, and it forms what we call a cosmic string.
“We have no idea whether cosmic strings actually were created in the early universe, but if they were and lasted up to the present time they could produce some fascinating effects. They would be infinitesimally thin — thinner than a proton — yet the mass density they carry would be enormous, up to a million million tons per centimeter. They might form the seeds around which matter collapses to form galaxies, for example. They would also ‘vibrate,’ producing not subspace harmonics but gravitational waves. Indeed, we may well detect the gravitational wave signature of a cosmic string before we ever directly observe the string itself.”
From The Physics of Star Trek (New York: HarperCollins, 1995), pp. 149-150.
Of course, what Landis, Forward and the other authors of the paper “Natural Wormholes as Gravitational Lenses” were talking about was not just a cosmic string, but one possessing negative mass, and it would have to wrap itself around a wormhole in order to stabilize it so it could survive to the present time. Do such structures exist? If so, it is possible that advances in both space-based and ground astronomy will eventually prove the point, but even then, we’ll be left to speculate about where or when such a wormhole might lead.
by Paul Gilster | Dec 28, 2005 | Breakthrough Propulsion, Culture and Society
Last week Centauri Dreams discussed the possible signature of a wormhole in astronomical data, as worked out in a 1994 paper titled “Natural Wormholes as Gravitational Lenses.” A wormhole moving between Earth and another star would show an odd but identifiable form of lensing — two spikes of light with a dip in the middle. But what would a wormhole look like if you could actually see it? Space artist Jon Lomberg had some thoughts on that and shared them in the following e-mail.
The wormhole entry was fascinating. I had the opportunity to try to visualize how a wormhole would look during the production of the film CONTACT. For the novel on which the film was based, Carl Sagan had asked Kip Thorne [Feynman Professor of Theoretical Physics at CalTech, and author of Black Holes and Time Warps: Einstein’s Outrageous Legacy] for guidance to keep the wormhole as scientifically plausible as possible. During the film’s production, I consulted with Kip to determine the appearance of a wormhole. Kip and his student Scott Hughes tried to calculate the paths of photons traveling through the wormhole, seen from outside the wormhole.
“Try not to make them look like black holes,” Kip advised. “It shouldn’t look like a vortex, a spinning accretion disk or anything like that.” Turns out that a wormhole doesn’t look like a hole at all. Rather than a hole in space, it would look like a blister in space, with a convex surface bulging out at you. A highly distorted, partially rotated image of the scenery on the other end might be discerned. Because of the large amount of negative energy required to keep the wormhole open, I envisioned some lensing distortions of the space around this side of the wormhole.
If you recall, once Ellie goes through the wormhole, she first emerges around Vega, gets a glimpse of the surroundings, and is almost immediately drawn into another wormhole, emerging over an icy moon orbiting an inhabited planet with a multiple star system in the sky. The following concept illustration [below] shows a wormhole approaching the viewer. A distorted image of the galactic center (the next stop) is seen on the convex shape of the wormhole’s mouth.
The image below is the scene she would travel into, a grand galactic panorama. A third wormhole is approaching in the distance, with a close view of the galactic center within it. This scene was cut, but the art in this sequence suggests how the wormhole could have appeared with digital graphics.
But at the conclusion of our work, the director and effects producer decided that the wormhole should not appear the way we had shown it, but should look like a vortex, exactly as Kip had cautioned against. Kip and I both hope that some future production will attempt to show these enigmatic objects in a way that distinuishes them from the very different phenomenon of a black hole.
Images: Copyright Jon Lomberg (www.jonlomberg.com).
