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Progress Toward the Dream of Space Drives and Stargates

by James F. Woodward

I first wrote about James Woodward’s work in my 2004 book Centauri Dreams: Imagining and Planning Interstellar Exploration, and have often been asked since to comment further on his research. But it’s best to leave that to the man himself, and I’m pleased to turn today’s post over to him. A bit of biography: Jim Woodward earned bachelor’s and master’s degrees in physics at Middlebury College and New York University (respectively) in the 1960s. From his undergraduate days, his chief interest was in gravitation, a field then not very popular. So, for his Ph.D., he changed to the history of science, writing a dissertation on the history of attempts to deal with the problem of “action-at-a-distance” in gravity theory from the 17th to the early 20th centuries (Ph.D., University of Denver, 1972).

On completion of his graduate studies, Jim took a teaching job in the history of science at California State University Fullerton (CSUF), where he has been ever since. Shortly after his arrival at CSUF, he established friendships with colleagues in the Physics Department who helped him set up a small-scale, table-top experimental research program doing offbeat experiments related to gravitation – experiments which continue to this day. In 1980, the faculty of the Physics Department elected Jim to an adjunct professorship in the department in recognition of his ongoing research.

In 1989, the detection of an algebraic error in a calculation done a decade earlier led Jim to realize that an effect he had been exploring proceeded from standard gravity theory (general relativity), as long as one were willing to admit the correctness of something called “Mach’s principle” – the proposition enunciated by Mach and Einstein that the inertial properties of matter should proceed from the gravitational interaction of local bodies with the (chiefly distant) bulk of the matter in the universe. Since that time, Jim’s research efforts have been devoted to exploring “Mach effects”, trying to manipulate them so that practical effects can be produced. He has secured several patents on the methods involved.

Jim retired from teaching in 2005. Shortly thereafter, he was diagnosed with some inconvenient medical problems, problems that have necessitated ongoing care. But, notwithstanding these medical issues, he passes along the good news that he remains “in pretty good health” and continues to be active in his chosen area of research. Herewith a look at the current thinking of this innovative researcher.

Travel to even the nearest stars has long been known to require a propulsion system capable of accelerating a starship to a significant fraction of the speed of light if the trip is to be done in less than a human lifetime. And if such travel is to be seriously practical – that is, you want to get back before all of your stay-behind friends and family have passed on – faster than light transit speeds will be needed. That means “warp drives” are required. Better yet would be technology that would permit the formation of “absurdly benign wormholes” or “stargates”: short-cuts through “hyperspace” with dimensions on the order of at most a few tens of meters that leave the spacetime surrounding them flat. Like the wormholes in the movie and TV series “Stargate” (but not nearly so long and without “event horizons” as traversable wormholes don’t have event horizons). With stargates you can dispense with all of the claptrap attendant to starships and get where you want to go (and back) in literally no time at all. Indeed, you can get back before you left (if Stephen Hawking’s “chronology protection conjecture” is wrong) – but you can’t kill yourself before you leave.

Starships and stargates were the merest science fiction until 1988. In 1988 the issue of rapid spacetime transport became part of serious science when Kip Thorne and some of his graduate students posed the question: What restriction does general relativity theory (GRT) place on the activities of arbitrarily advanced aliens who putatively travel immense distances in essentially no time at all? The question was famously instigated by Carl Sagan’s request that Thorne vet his novel Contact, where travel to and from the center of the galaxy (more than 20,000 light years distant) is accomplished in almost no time at all. Thorne’s answer was wormholes – spacetime distortions that connect arbitrarily distant events through a tunnel-like structure in hyperspace – held open by “exotic” matter. Exotic matter is self-repulsive, and for the aforementioned “absurdly benign” wormholes, this stuff must have negative restmass. Not only does the restmass have to be negative, to make a wormhole large enough to be traversable, you need a Jupiter mass (2 X 1027 kg) of the stuff. This is almost exactly one one thousandth of the mass of the Sun and hundreds of times the mass of the Earth. In your livingroom, or on your patio. Warp drives, in this connection at least, are no better than wormholes. Miguel Alcubierre, in 1994, wrote out the “metric” for a warp drive; and it too places the same exotic matter requirement on would be builders.

Long before Thorne and Alcubierre laid out the requirements of GRT for rapid spacetime transport, it was obvious that finding a way to manipulate gravity and inertia was prerequisite to any scheme that hoped to approach, much less vastly surpass the speed of light. Indeed, in the late 1950s and early 1960s the US Air Force sponsored research in gravitational physics at Wright Field in Ohio. As a purely academic exercise, the Air Force could have cared less about GRT. Evidently, they hoped that such research might lead to insights that would prove of practical value. It seems that such hopes were not realized.

If you read through the serious scientific literature of the 20th century, until Thorne’s work in the late ‘80s at any rate, you will find almost nothing ostensibly relating to rapid spacetime transport. The crackpot literature of this era, however, is replete with all sorts of wild claims and deeply dubious schemes, none of which are accompanied by anything resembling serious science. But the serious (peer reviewed) scientific literature is not devoid of anything of interest.

If you hope to manipulate gravity and inertia to the end of rapid spacetime transport, the “obvious conjecture” is that you need a way to get some purchase on gravity and inertia. Standard physics, embodied in the field equations of Einstein (GRT) and Maxwell (electrodynamics), seems to preclude such a possibility. So that “obvious conjecture” suggests that some “coupling” beyond that contained in the Einstein-Maxwell equations needs to be found. And if we are lucky, such a coupling, when found, will lead to a way to do the desired manipulations. As it turns out, there are at least two instances of such proposed couplings advanced by physicists of impeccable credentials. The first was made by Michael Faraday – arguably the pre-eminent experimental physicist of all time – in the 1840s. He wanted to kill the action-at-a-distance character of Newtonian gravity (that is, its purported instantaneous propagation) by inductively coupling it to electromagnetism (which he had successfully shown to not be an action-at-a-distance interaction by demonstrating the inductive coupling of electricity and magnetism). He did experiments intended to reveal such coupling. He failed.

The second proposal was first made by Arthur Schuster (President of the Royal Society in the 1890s) and later Patrick M.S. Blackett (1947 Nobel laureate for physics). They speculated that planetary and stellar magnetic fields might be generated by the rotational motion of the matter that makes them up. That is, electrically neutral matter in rotation might generate a magnetic field. Maxwell’s electrodynamics, of course, makes no such prediction. There were other proposals. In the 1930s and ‘40s Wolfgang Pauli and then Erwin Schrodinger constructed five-dimensional “unified” field theories of gravity and electromagnetism that predicted small coupling effects not present in the Einstein-Maxwell equations. But the Schuster-Blackett conjecture is more promising as the effects there are much larger – large enough for experimental investigation. And George Luchak, a Canadian graduate student (at the time), had written down a set of coupled field equations for Blackett’s proposal.

Some worthwhile experiments can be done with limited means in a short time but only a fool tries to do serious experiments without having a plausible theory as a guide. Plausible theory does not mean Joe Doak’s unified field theory. It means theory that only deviates from standard physics in explicit, precise ways that are transparent to inspection and evaluation. (The contra positive, by the way, is also true.) So, armed with Faraday’s conjecture and then the Schuster-Blackett conjecture and Luchak’s field equations, in the late 1960s I set out to investigate whether they might lead to some purchase on gravity and inertia. The better part of 25 years passed doing table-top experiments and poking around in pulsar astrophysics (with its rapidly rotating neutron stars with enormous magnetic fields, pulsars are the ultimate test bed for Blackett’s conjecture) to see whether anything was there. Suggestive, but not convincing, results kept turning up. In the end, nothing could be demonstrated beyond a reasonable doubt – the criterion of merit in this business. However, as this investigation was drawing to a close, about the time that Thorne and others got serious about traversable wormholes, detection of an algebraic error in a calculation led to serious re-examination of Luchak’s formalism for the Blackett effect.

Luchak, when he wrote down his coupled field equations, had been chiefly interested in getting the terms to be added to Maxwell’s electrodynamic equations that would account for Blackett’s conjecture. So, instead of invoking the full formal apparatus of GRT, he wrote down Maxwell’s equations using the usual four dimensions of spacetime, and included a Newtonian approximation for gravity using the variables made available by invoking a fifth dimension. He wanted a relativistically correct formalism, so his gravity field equations included some terms involving time. They were required because of the assumed speed of light propagation velocity of the gravity field – where Newton’s gravity theory has no time-dependent terms as gravity “propagates” instantaneously. You might think all of this not particularly interesting, because it is well-known that special relativity theory (SRT) hasn’t really got anything to do with gravity – notwithstanding that you can write down modified Newtonian gravity field equations that are relativistically correct (technospeak: “Lorentz invariant”).

But this isn’t quite right. Special relativity has inertia implicitly built right into the foundations of the theory. Indeed, SRT is only valid in “inertial” frames of reference.[ref]Inertial reference frames are those in which Newton’s first law is valid for objects that do not experience external forces. They are not an inherent part of spacetime per se unless you adhere to the view that spacetime itself has inertial properties that cause inertial reaction forces. This is not the common view of the content of SRT where inertial reaction forces are attributed to material objects themselves, not the spacetime in which they reside.[/ref] So, consider the most famous equation in all physics (that Einstein published as an afterthought to SRT): E=mc2. But write it as Einstein first did: m=E/c2. The mass of an object – that is, its inertia – is equal to its total energy divided by the square of the speed of light. [Frank Wilczek has written a very good book about this: The Lightness of Being.] If inertia and gravity are intimately connected, then since inertia is an integral part of SRT, gravity suffuses SRT, notwithstanding that it does not appear explicitly anywhere in the theory.[ref] As a technical note it is worth mentioning that in GRT inertial reaction forces arise from gravity if space is globally flat, as in fact it is measured to be, and global flatness is the distinctive feature of space in SRT. This, however, does not mean that spacetime has inherent inertial properties.[/ref] Are gravity and inertia intimately connected? Einstein thought they were. A well known part of this connection is the “Equivalence Principle” (that inertial and gravitational forces are the same thing) but there is an even deeper notion needing attention. He gave this notion its name: Mach’s principle, for Einstein attributed the idea to Ernst Mach (of Mach number fame).[ref] Another technical note: spacetime figures into the connection between gravity and inertia as the structure of spacetime is determined by the distribution of all gravitating stuff in the universe in the field equations of GRT. So if gravity and inertia are the obverse and reverse of the same coin, the structure of spacetime is automatically encompassed. Spacetime per se only acquires inertial properties if it is ascribed material properties – that is, it gravitates. Interestingly, if “dark energy” is an inherent property of spacetime, it gravitates.[/ref]

What is Mach’s principle? Well, lots of people have given lots of versions of this principle, and protracted debates have taken place about it. Its simplest expression is: Inertial reaction forces are produced by the gravitational action of everything that gravitates in the universe. But back in 1997 Herman Bondi and Joseph Samuel, answering an argument by Wolfgang Rindler, listed a dozen different formulations of the principle. Generally, they fall into one of two categories: “relationalist” or “physical”. In the relationalist view, the motion of things can only be related to other things, but not to spacetime itself. Nothing is said about the interaction (via fields that produce forces) of matter on other matter. The physical view is different and more robust as it asserts that the principle requires that inertial reaction forces be caused by the action of other matter, which depends on its quantity, distribution, and forces, in particular, gravity, as well as its relative motion. [Brian Greene not long ago wrote a very good book about Mach’s principle called The Fabric of the Cosmos. Alas, he settled for the “relationalist” version of the principle, which turns out to be useless as far as rapid spacetime transport is concerned.]

The simplest “physical” statement of the principle, endorsed by Einstein and some others, says that all inertial reaction forces are produced by the gravitational action of chiefly the distant matter in the universe. Note that this goes a good deal farther than Einstein’s Equivalence Principle which merely states that the inertial and gravitational masses of things are the same (and, as a result, that all objects “fall” with the same acceleration in a gravity field), but says nothing about why this might be the case. Mach’s principle provides the answer to: why?

Guided by Mach’s principle and Luchak’s Newtonian approximation for gravity – and a simple calculation done by Dennis Sciama in his doctoral work for Paul Dirac in the early 1950s – it is possible to show that when extended massive objects are accelerated, if their “internal” energies change during the accelerations, fluctuations in their masses should occur. That’s the purchase on gravity and inertia you need. (Ironically, though these effects are not obviously present in the field equations of GRT or electrodynamics, they do not depend on any novel coupling of those fields. So, no “new physics” is required.) But that alone is not enough. You need two more things. First, you need experimental results that show that this theorizing actually corresponds to reality. And second, you need to show how “Mach effects” can be used to make the Jupiter masses of exotic matter needed for stargates and warp drives. This can only be done with a theory of matter that includes gravity. The Standard Model of serious physics, alas, does not include gravity. A model for matter that includes gravity was constructed in 1960 by three physicists of impeccable credentials. They are Richard Arnowitt (Texas A and M), Stanley Deser (Brandeis), and Charles Misner (U. of Maryland). Their “ADM” model can be adapted to answer the question: Does some hideously large amount of exotic matter lie shrouded in the normal matter we deal with every day? Were the answer to this question “no”, you probably wouldn’t be reading this. Happily, the argument about the nature of matter and the ADM model that bears on the wormhole problem can be followed with little more than high school algebra. And it may be that shrouded in everyday stuff all around us, including us, is the Jupiter mass of exotic matter we want. Should it be possible to expose the exotic bare masses of the elementary particles that make up normal matter, then stargates may lie in our future – and if in our future, perhaps our present and past as well.

The physics that deals with the origin of inertia and its relation to gravitation is at least not widely appreciated, and may be incomplete. Therein lie opportunities to seek new propulsion physics. Mach’s principle and Mach effects is an active area of research into such possibilities. Whether these will lead to propulsion breakthroughs cannot be predicted, but we will certainly learn more about unfinished physics questions along the way.

REFERENCES

More technical and extensive discussions of some of the issues mentioned above are available in the peer reviewed literature and other sources. A select bibliography of some of this material is provided below. Here at Centauri Dreams you will shortly find more recent and less technical treatments available. They will be broken down into three parts. One will deal with the issues surrounding the origin of inertia and the prediction of Mach effects [tenatively titled “Mach’s principle and Mach effects”]. The second will present recent experimental results [tentatively titled “Mach effects: Recent experimental results”]. And the third will be an elaboration of the modifications of the ADM model that suggest exotic matter may be hiding in plain sight all around us [tentatively titled “Stargates, Mach’s principle, and the structure of elementary particles”]. The first two pieces will not involve very much explicit mathematics. The third will have some math, but not much beyond quadratic equations and high school algebra.

  • Books:

Greene, Brian, The Fabric of the Cosmos: Space, Time, and the Texture of Reality (Knopf, New York, 2004).

Sagan, Carl, Contact (Simon and Schuster, New York, 1965).

Wilczek, Frank, The Lightness of Being: Mass, Ether, and the Unification of Forces (Basic Books, New York, 2008).

  • Articles:

Alcubierre, M., “The warp drive: hyper-fast travel within general relativity,” Class. Quant. Grav. 11 (1994) L73 – L77. The paper where Alcubierre writes out he metric for warp drives.

Arnowitt, R., Deser, S., and Misner, C.W., “Gravitational-Electromagnetic Coupling and the Classical Self-Energy Problem,” Phys. Rev. 120 (1960a) 313 – 320. The first of the ADM papers on general relativistic “electrons”.

Arnowitt, R., Deser, S., and Misner, C.W., “Interior Schwartzschild Solutions and Interpretation of Source Terms,” Phys. Rev 120 (1960b) 321 – 324. The second of the ADM papers.

Bondi, H. and Samuel, J., “The Lense-Thirring effect and Mach’s principle,” Phys. Lett. A 228 (1997) 121 – 126. One of the best papers on Mach’s principle.

Luchak, George, “A Fundamental Theory of the Magnetism of Massive Rotating Bodies,” Canadian J. Phys. 29 (1953) 470 – 479. The paper with the formalism for the Schuster-Blackett effect.

Morris, M.S. and Thorne, K. S., “Wormholes in spacetime and their use for interstellar travel: A tool for teaching general relativity,” Am. J. Phys. 56 (1988) 395 – 412. The paper where Kip Thorne and his then grad student Michael Morris spelled out the restrictions set by general relativity for interstellar travel. Their “absurdly benign wormhole” solution is found in the appendix on page 410.

Sciama, D. “On the Origin of Inertia,” Monthly Notices of the Royal Astronomical Society 113 (1953) 34 – 42. The paper where Sciama shows that a vector theory of gravity (that turns out to be an approximation to general relativity) can account for inertial reaction forces when certain conditions are met.

Woodward, J.F., “Making the Universe Safe for Historians: Time Travel and the Laws of Physics,” Found. Phys. Lett. 8 (1995) 1 – 39. The first paper where essentially all of the physics of Mach effects and their application to wormhole physics is laid out.

  • Other sources for Mach effects and related issues

“Flux Capacitors and the Origin of Inertia,” Foundations of Physics 34, 1475 – 1514 (2004). [Appendicies give a line-by-line elaboration of the derivation of Mach effects, and a careful evaluation of how Newton’s second law applies to systems in which Mach effects are present.]

“The Technical End of Mach’s Principle,” in: eds. M. Sachs and A.R. Roy, Mach’s Principle and the Origin of Inertia (Apeiron, Montreal, 2003), pp. 19 – 36. [Contributed paper for a commemorative volume for the 50th anniversary of the founding of the Kharagpur campus of the Indian Institute of Technology. It is the only published paper where the wormhole term in Mach effects was sought.]

“Are the Past and Future Really Out There,” Annales de la Fondation Louis de Broglie 28, 549 – 568 (2003). [Contributed paper for a commemorative issue honoring the 60th anniversary of the completion of Olivier Costa de Beauregard’s doctoral work with Prince Louis de Broglie. The instantaneity of inertial reaction forces, combined with the lightspeed restriction on signal propagation of SRT, suggest that the Wheeler-Feynman “action-at-a-distance” picture of long range interactions is correct. This picture suggests that the past and future have some meaningful objective physical existence. This is explored in this paper, for Olivier Costa de Beauregard was one of the early proposers of the appropriateness of the action-at-a-distance picture in quantum phenomena.]

  • Presentations

Presentations at STAIF and SPESIF (most with accompanying papers in the conference proceedings) yearly since 2000.

Presentation at the Society for Scientific Exploration meeting in June, 2010, now available in video format on the SSE website.

Presentation: Why Science Fiction has little to fear from Science, at the 75th Birthday Symposium for John Cramer, University of Washington, September 2009.

  • Radio Interviews

The Space Show [3/20/2007]

The Space Show [3/3/2009]

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Comments on this entry are closed.

  • Marc G Millis May 23, 2011, 10:50

    Here is another good reference that documents discussions about unsolved physics of inertial frames:

    Barbour & Pfister (eds) (1995) ‘Mac’s Principle, from Newton’s Bucket to Quantum Gravity.’ Vol 6 of Einstein Studies, The Center for Einstein Studies, Birkhäuser, Boston MA.

  • henk May 23, 2011, 12:01

    is it really that easy to go faster than light. That there is some kind of exotic matter waiting to be discoverd that we can move faster than light. We can not even travel close to lightspeed and now we are already trying to break it. I know it is all Speculative work. But i do get why we want to break it. If we can not break it. We will probably be trapped in our galactic neighborhood.
    Or we have to travel a long time.

  • James M Essig May 23, 2011, 12:22

    Hi Paul and James;

    This article is truely inspirational and hope instilling.

    If my memory serves me correct, one of Stephen Hawkings concepts involves a condition where the very future ending boundary condition of our universe would be equivalent to its initial condition in such a manner that the notion of a universe which began at a definate point in time would not have meaning. The beginning of the universe and its end would be indistinguishable in a manner analogous to the indistinquishability between say electrons.

    An interesting take on the above notion of Hawking’s involves the concept of accelerating inertially to an extreme gamma with tolerable or made tolerable accelerations. The craft would travel forward in time at near light speed to the no-temporal boundary condition of any future big crunch and would somehow travel past the future to return to the past no temporal boundary condition. Enabling the craft to survive the topological transition region would take some doing, but if Hawking’s idea is correct, then the subject method should be possible in theory providing the obvious caveats can be overcome.

    Another idea I have been toying around with is that of exactly light speed travel for inertial reference frame space craft. Accordingly, the crew would experience a temporal eternity go by while only one Planck Time Unit past aboard the space craft. Since the Planck Time Unit may be the smallest portion of time that has any meaning, the craft would seem to need to at least travel one Planck Time Unit and no less ship time. The craft relative to a background observer would destructively interact with the interstellar medium after having traveled a local distance such as by being absorbed, scattered, or otherwise interfered with by the interstellar medium. To we background observers, the craft would be ablissimated while to the space craft observers, the craft would travel just fine an infinite number of light-years and an infinite time into the future on just one Planck Time Unit, or greater infinite distances in more than one Planck Time Unit ship time.

    This notion is analogous to the notion that an object falling into a blackhole such as a human crewed space craft could experience entering the region within the event horizon while approaching the central singularity, while to an outside observer, the space craft would appear completely smeared out an blended over the event horizon. Both observations would be real. This conjecture was made by prominent black hole thermodynamicists recently as a way to deal with holographic information theory.

    In a way, high gamma factor travel is also inertially coupled to general relativity theory when one considers that a space craft traveling at near light speed for a long enough time will suddening exceed the speed of light in its recessional velocity from the Milky Way. Galaxies traveling at Newtonian velocities through space that are imaged as having a redshift factor of about two are alreadly receeding from the Milky Way at superluminal recessional velocities due to universal space time expansion.

  • Alexander May 23, 2011, 12:40

    Thank you for posting, Dr. Woodward. I’ve been following your work with interest and look forward to hearing more in your future articles.

  • Ron S May 23, 2011, 14:43

    A few small comments on what I read here.

    Einstein did not “endorse” Mach’s Principle or use it in GRT. The historical record (see Pais, for example) and the EFE themselves, are I thought pretty clear about this. It is true that in his early work on gravitation Einstein was quite taken with Mach’s idea since he needed to firmly establish the foundations of his future theory. He soon dropped it since it was unnecessary and therefore superfluous. This wasn’t the only “principle” Einstein toyed with and then abandoned in his quest for a successful theory.

    SRT does handle non-inertial frames (acceleration but not gravitation), although the maths gets really ugly.

    FTL is simply time travel and nothing more. It says nothing, and can say nothing, about the proper time of a space-like trajectory. You may get back to your unaged twin, and even your dinner on time, but we can say nothing at this point about how much the traveling twin will have aged; that is, the duration of the voyage. I touched on this in a comment in a thread a couple of week’s back.

    All those 5-D theories of mid-20th century came to dead ends, including Einstein’s own work on UFT. Not only was it seemingly impossible to incorporate EM into a classical field theory, even that was pointless since it did not incorporate the strong and weak forces, and many experimental phenomena of QM besides. String theory is in a sense the modern incarnation of that work, which may or may not be more successful in unifying physics.

  • Greg May 23, 2011, 16:37

    Very nice article. I enjoy more the fact that there are still new and un-thought of questions to the world around us. Even if we were to discover that the world/universe is full of exotic matter, that still would not mean wormhole travel can be done. I’m curious as to what other qualities that exotic matter might have and what they could be used for.

  • Daniel Suggs May 23, 2011, 17:08

    Paul, I look forward to your future articles on this. After three times trying, I can’t seem to get my head around this, but it sounds too interesting to give up trying to comprehend. Perhaps you can simplify it a little.
    It is probably way too early to ask this question, but: Would there need to be a receiving ‘gate’ at the other end? If so, it will still be a very long time before any travel could happen. If not, then I am ready to transport. LOL. Thanks again for providing this site.

  • Rogério Penna May 23, 2011, 18:50

    Very interesting and hopefuly correct, but I fear Woodward should drop any mention to propellantless propulsion or “faster than light” transportation from his research, even if ME research leads to that. These subjects dont fall well with the scientific community and may hinder research, since interested respected people might avoid the subject so as to not be connected with these two taglines.

    Concentrate on the pure subject of mass fluctuations and proving them beyond any doubt, without reference to the implications. That alone can lead to a Nobel. The rest (the possible uses as propulsion) will come naturally, and in an easier way.

  • Paul Gilster May 23, 2011, 20:36

    Daniel Suggs writes:

    Would there need to be a receiving ‘gate’ at the other end?

    I’m afraid the answer to that question is well beyond my powers! But I agree with you that it’s way too early to ask — we have so much to learn about what’s even remotely possible.

  • kurt9 May 23, 2011, 20:40

    I’ve been following Woodward’s research for about 2 years. Of all of the potential breakthrough propulsion concepts, I find his to be the most credible.

  • Dan Ibekwe May 23, 2011, 20:53

    “all of the claptrap attendant to starships”

    Whoa, Dr Woodward, I *like* starships! If we’re going on safari to Gliese 581D might it not be a good idea to bring a ship (= liveable habitat) along with us? All that atmospheric cyanogen makes my eyes water and the nitric acid rain plays merry hell with gore-tex.

    Seriously, this is breathtaking and exciting stuff. It’s good to know there are still possibilities that the speed of light is not the final limit.

  • Interstellar Bill May 23, 2011, 22:51

    Any practical demonstration of FTL would constitute an ironclad guarantee that we are Alone, since FTL enables exponential population growth to gobble up an entire Cosmos, however huge, in astrophysically short durations.

    Our list of high-energy technologies is woefully short
    when considered as candidates for breaking out into FTL-Land.
    Diamond anvils, superconducting magnets, particle accelerators, laser banks, and nuclear detonations — you can list more, but where is any phenomenon that could leverage our puny baryonic bodies to have StarShip Controls?
    Odds are that the requisite physics isn’t discoverable on a planet anyway, since it would most plausibly require an apparatus the size of the Moon’s orbit, located beyond Pluto.
    The odds are even greater than any FTL will be even more energetically expensive and engineering-troublesome than conventional starflight, ending up being reserved only for the most urgent interstellar cargoes.

    Just as atheists urge others to abandon their idea of God,
    I urge the abandonment of allegiance to two big SF ideas I long loved as much as anyone:
    FTL and aliens.
    (Don’t stop SETI or FTL theorizing, however,
    just don’t have much hope for either.)

    Instead, consider a realistic motto for afficianados of interstellar Travel
    SEMPER SUB-CEE

  • Steve Pease May 23, 2011, 23:27

    The link to the Presentation didn’t work for me.

  • Paul Gilster May 24, 2011, 7:39

    Steve, try it again. I just checked and updated the link.

  • stephen May 24, 2011, 12:59

    I just had an idea.

    We have a bipolar, or bimodal, idea about matter, and mass.
    We can have matter or antimatter, and we can have mass or negative mass.

    But what if there are other possibilities? Not just positive/negative, but other…modes?

    Maybe the idea of just two possibilities for mass–positive or negative–is too limited. There may be positive, negative, and hundreds of other…modes.

    I wonder if I made that clear? I have no evidence or math to back it up, but the universe keeps getting more and more complicated. We keep coming up with new particles and forces to explain our observations…not unlike how astrologers kept coming up with epicycles within epicycles to explain their observations…but I’m sure that’s just a coincidence….

  • jkittle May 24, 2011, 13:07

    Bill
    I am with you. I think the technology for living in “exotic ” environments like on a kuiper belt object is far more achievable than FTL. With advanced Life support, Bioengineering , Deuterium Fusion and Ion drives we could inhabit the stars, or at least the worlds between them. There is so much room to expand if we stay with the dwarf worlds, building civilizations analogous to the island hopping Greeks or Polynesians. If we expand slowly outward, our many generations-past grandchildren may have little interest in the deep gravity-well worlds like Earth, even if we find them circling distant stars. Instead, the small worlds orbiting/clustered in the shallow wells of a brown dwarfs may be preferred. With sufficient energy for fusion, who needs the sun? With Bioengineering who needs aliens! I do congratulate Dr Woodward on his attempts to bring some clarity and credibility to the field and especially his attempts to achieve some scientific “purchase” on the problem of Faster-than-light phenomena. The odd observation is followed by theory which is followed by engineering! We have plenty of odd observations still alive and untamed today -from dark matter and dark energy to Fermi’s Paradox . All part of the same mix, in my mind!

  • Tobias Holbrook May 24, 2011, 14:21

    “The odds are even greater than any FTL will be even more energetically expensive and engineering-troublesome than conventional starflight, ending up being reserved only for the most urgent interstellar cargoes.”
    Or information – even if cargo is running at a million credits per gram-parsec, how much information could that contain? Or, even if we only manage subatomic wormholes… photons can still slip through, so we still get our Ansible (of course, your receiver will fail if you try sending information back in time).

    Depending on the cost of FTL, we could end up with fast, sublight travel being used f0r cargo and passenger travel, and small craft massing a few grams carrying news around the network.

  • Alexander May 24, 2011, 16:07

    There’s no need to ship cargo around sublight. Any cargo can be manufactured on-site using standard technology and locally available materials and energy.

    If uploading ever becomes feasible, better to ship passengers as data using FTL crafts as you suggested.

  • Mindrust May 24, 2011, 16:49

    “Any practical demonstration of FTL would constitute an ironclad guarantee that we are Alone, since FTL enables exponential population growth to gobble up an entire Cosmos, however huge, in astrophysically short durations.”

    Even with FTL, the universe is a really big place. And you’re assuming a lot here about the trends of an advanced civilization; something we know virtually nothing about. It’s never a good idea to speak in absolutes when talking about hypothetical advanced civilizations. However, maybe by the time an advanced civilization obtains technology to extend their lifespan indefinitely via artificial augmentation, their population growth slows down tremendously.

    I personally feel there may just be few advanced civilizations in our galaxy and the universe in general. But one thing seems for certain, if Woodward’s right and it is possible to build stargates and space drives, then we should probably start paying closer attention to those 5% of unexplained objects we encounter in the sky.

  • Rob Henry May 24, 2011, 17:28

    Interstellar Bill, it is interesting that you so completely discount some estimates of abiogenesis that would only place de novo generation of life as ten to the power of tens of thousands to one against on each receptive planet. With such estimates of abiogenesis, and even if FTL travel was very expensive per star gate location but practical, there are several ways that you could still model a universe whose filling was yet to reach completion today, so it is worth looking at the evidence that you already know.

    Firstly if you believe evolution the key to biology you must also believe that no elaborate biologically useful function can be gained except through the agency of ancestral lines of living organisms. This is simply Darwin’s principles stated in an atypical fashion (many biologist before and after believed that elaborate useless structures could just slowly form if they might become useful to later life). Now note that of all life’s functions, reproduction is the only one that we still can’t even design a machine to do today. Note further that for von Neumann, to show that non-trivial replication was even possible by naturalistic means, had to use a mathematical universe designed for that purpose, and even then that mechanism was too complex for him to outline in detail (he had to be content to show it possible). Note still further that the core of modern biochemistry that can reproduce includes the translation mechanisms, which, to me, is by far the most complex process in all of biochemistry. Note that no known life uses anything simpler, and that evolution heavily selects for simplicity. Finally note (and to me this is the key to the confusion) that biology is a refuge for those who love science but hate mathematics, and the study of ‘chemical evolution’ used to be dominated by Marxists who believe in the supernatural matter organising forces implied by dialectic materialism.

    When you really think about it, all (naturalistic) science points to us being so very much alone as to allow some FTL schemes.

  • Mekraab May 24, 2011, 18:10

    “Any practical demonstration of FTL would constitute an ironclad guarantee that we are Alone”

    No it would only mean we’re the first, or among the first to develop FTL. If science teaches us anything it’s that we aren’t special

    “FTL is simply time travel and nothing more”

    and if an alcubierre style warp drive were ever created then what?

  • Interstellar Bill May 24, 2011, 18:51

    Rob Henry
    The most promising models of abiogenesis posit its site to be in the micron-sized pores of Hadean ocean-floor volcanic ‘smokers’, where steep gradients of temperature and pH enabled self-catalyzing protolife to arise in those pores and then evolve into true cells with membranes. Said cells finally leave their home pores for free-living in the ocean. The two major schools, of Russell and Wasterschauser, are sufficiently similar for astrobiological optimism that microscopic life would arise with biochemical design features very similar to ours. The universal reliance of terrestrial life upon proton gradients and upon a core set of 500 chemical species is circumstantial evidence of abiogenesis here, rather than the cosmic reservoir posited by Hoyle & Wickramasinghe.

    This pore-genesis idea relies upon the catalytic powers of iron, nickel, and zinc when found on said pore surfaces. The ironic astrobiological consequence, so far unappreciated, of this idea is that the proto-Earth had all its iron sink to the core, shortly after the Moon-creating Giant Collision. There was none on the surface available toplay the essential catalyst in both above-mentioned schools of pore-abiogenesis. No surface iron, that is, until after the Late Giant Bombardment, which included enough asteroidal iron for today’s commercial deposits as well as for Hadean life to start. Said Bombardment was a side-effect of an orbital hiccup by the outer Giant Planets, as elucidated in the now-canonical Nice model. Without it, no Bombardment, no iron deposits, no abiogenesis.

    So, dear fellow astrobiological enthusiast Rob Henry,
    the rarity you suspect of abiogenesis is indeed highly likely,
    but not due to the statistical improbabilites calculated
    for abiogenesis in such open solutions as the ‘warm soup’,
    but due to the rarity of terrestrial planets with surface iron.

    All you need is to run volcanic emissions through said ocean-floor iron-deposits, and you’ll get enough spontaneous RNA to kick-start life every time.
    The probability bottle-neck, dear Rob, is not at abiogenesis but at its catalytic requirements for iron and zinc, which normally are locked in planetary cores.

    When you do get life, just add 10% or more of oxygen and presto, multicellularity. Once you have vision then animal consciousness is inevitable, and verterbrates inevitably invent mylenation, which enables big brains. Those, I believe, would be rare but highly likely, once given some admittedly rare combination of preconditions that reward big brains with more children, as was in our case.

    Big-brained intelligent life will inevitably arise elsewhere, but only after some very rare preconditions are fulfilled. As rare as successive lottery winnings, so rare as to require this enormous universe just for one –WE.

  • Ron S May 24, 2011, 20:02

    Me: “FTL is simply time travel and nothing more”

    Mekraab: and if an alcubierre style warp drive were ever created then what?

    Then what? There is no Alcubierre drive of any sort, nor can there be as has been described, and perhaps not possible at all. Even so it doesn’t matter. The lack of understanding of FTL among the general public is understandable, but among interstellar travel enthusiasts? I’m disappointed.

  • Rob Henry May 24, 2011, 20:58

    Interstellar Bill, I am glad to see that you have so thoroughly followed the details of abiogenesis – my above comment was more akin to a meta-analysis and explanation as to why I think that all possible schemes are doomed to find life stupendously unlikely. I would like to state here and now that if there is an exception it will turn out to be through a very detailed and elaborate path, and give the impression that it is written into the laws of our particular universe.

    Many of your above mentioned examples have been of great interest to me as I look to find if there is an exception, but of one in particular I know nothing. Do you have any references to the details of this core set of 500 chemical argument. If this is anything other than just gently suggestive I am very interested, and if otherwise I’m still quite curious.

    Also, let me I issue a warning to your own studies. Think how often uncharged nucleic acids such as peptide nucleic acid are studied as possible precursors to DNA or RNA. Now just think how ridiculous that is. To store and replicate information with high fidelity, hydrogen bonding must bind a codon to its anticodon very tightly. If an information storing array of these residues exists their proximity either means that the combined attraction is so strong that these sheets can’t be separated or a mechanism exists whereby another force separates each whole sheet or strand from the other rather than just than just one residue from its codon. Only a charged backbone will foot the bill so these investigations demonstrate blind desperation.

  • Rob Henry May 24, 2011, 21:25

    Oops, I meant to imply that some prebiotic chemistry studies have been distorted by desperation, not all of them.

  • John Q May 24, 2011, 22:39

    I’m echoing Ron S here: to speak intelligently about FTL, you have to have a coherent space-time framework to guide your thinking. Such a framework would be radically different from what we have now, yet be able to reproduce the whole of contemporary physics (especially causality), plus produce new results/predictions. This is a very tall order, one comparable to Einstein’s original achievement at the very least. No such theory exists, though people have speculated that a full and complete theory of Quantum Gravity would give birth to a new theory of space-time, perhaps just what is needed.

    But who knows. Whether such a theory would yield as a consequence anything resembling practical FTL is anyone’s guess. So it remains true is that Going FTL means Going BIT (backwards in time) with results that are unpredictable to say the least. How, for example, does one astrogate as we pilot our ship into the past? I don’t know how to even talk about such a thing let alone do it. Will simultaneity make a come back? The mind reels.

    Now no one should be discouraged from radical space-time speculations, of course, but an appreciation of the magnitude of the problem is a prerequisite for doing so. My own feeling is there are so many opportunities and problems in the Sub-C-level domain that fretting about FTL is for now unnecessary. Most near-term issues with space-flight are economic more than anything else. I’ve spent a lot of time reading about economics (almost as much as physics) and trust me, the rumors are true: it will bum you out.

  • Marc G Millis May 25, 2011, 6:59

    For those who are skeptical about such things, please remember at lest these two things:
    (1) Skepticism is most useful when identifying key questions to shed light on that line between what is known and where the knowledge gaps still reside – to make sure we are getting reliable knowledge. When skepticism is just blanket statements to the effect of “that won’t work” then it is NOT skepticism, but pedantic disdain.
    (2) Regardless of whether the desired idea works, value will be gained by pursuing such ideas so long as the focus is on understanding nature as it truly is, instead of how we would like it to be or instead of how we think it is based on only the past.

  • Marc G Millis May 25, 2011, 7:19

    Regarding the history of Mach’s principle and what Einstein attempted, it is difficult to get to the heart of the matter through some of the more ‘summary’ publications. My recollection of more varied reading (memory worth doubting) is that Einstein attempted to incorporate Mach’s principle and that it did not work out for him. The equations that he came up with – based on Riemannian geometry – cannot address such more global questions. Riemannian treatments are inherently LOCAL, not global. Whether this is indicative of the irrelevance of Mach’s Principle, or of the incomplete nature of GR remains to be seen. As an example of a relevant open area in GR, consider conservation of momentum with either warp drives or wormholes. The answers on those are not yet out. Thought experiments about those spaceflight notions can bring such lingering unknowns under more systematic scrutiny. Who knows, yet, how the final answers will turn out.

  • Ron S May 25, 2011, 11:35

    Marc, I agree with everything you’ve said. First, no disdain from me on exploration of new physics by means of asking interesting questions. Just so long as we do not ignore what we do know (in line with John Q’s comment).

    Second, regarding Mach and Einstein, I like Pais’ coverage of the topic since he really dissects the historical record and digs deep into what questions Einstein was struggling with. I think what you are alluding to with the local treatment of gravitation (which is quite true) is that Mach’s Principle introduced a global aspect, namely a preferred or absolute reference frame. While at first it seemed to solve certain questions of inertia it also violated his preference for no preferred frame (same laws of physics for everyone, everywhere) and, ultimately, entirely coordinate-free set of field equations.

    This seemed to be the right approach since, so far at least, there is no good evidence of a preferred frame in our universe. Experiments to date also show no distinction between inertial and gravitational mass, although the precision and energy domains of the experiments is not great.

  • Paul Gilster May 25, 2011, 13:48

    I second Ron S’s admiration for Pais, a splendid resource!

  • Bynaus May 25, 2011, 16:16

    Two claims, same argument :)

    Interstellar Bill: “Any practical demonstration of FTL would constitute an ironclad guarantee that we are Alone, since FTL enables exponential population growth to gobble up an entire Cosmos, however huge, in astrophysically short durations.”

    If there ever was a single civilization with exponential population growth, gobbeling up the entire cosmos in the process, chances for a typical observer of that universe NOT to be part of this civilization would be ridiculously small. Planet-based civilizations like ours would constitute an extremly untypical perspective on the universe. However, the principle of mediocrity affords that we are, with high probability, typical observers of the universe. If FTL is possible, it will therefore not enable extreme, cosmos-wide exponential population growth – for whatever reason.

    Mekraab: “No it would only mean we’re the first, or among the first to develop FTL. If science teaches us anything it’s that we aren’t special”

    How can we be among the first civilizations in the universe and NOT be special? The principle of mediocrity would have us appear somewhere in the broad middle of all civilizations.

    The most optimistic answer to the FTL-enhanced Fermi-paradoxon is that civilizations per se are extremely rare. The pessimistic answer is that all civilizations are bound to self-destruct, for a reason that is not (yet?) completly clear to us. The middle ground may be a universe where civilizations are very few and far inbetween, but are able to meet using FTL (wormhole-networks) only in the very far future of the universe.

  • Marc G Millis May 25, 2011, 17:43

    Ron S;

    Thanks for pointing me to Pais !

    Regarding: “there is no good evidence of a preferred frame in our universe.” – Note that the Cosmic Microwave Background Radiation does provide an effective absolute reference frame by virtue of the Doppler shifts (for/aft) observed when moving through it. I regret I do not have a ref citation handy. Now, to be precise, I’m offering that only in the context of a thought-provoking natural phenomenon. The more rigorous implications to this topic are one too much for a comments post. It makes me realize I should probably finish and submit some more papers. Not sure what sort of relevance this has to the topic, but it is at least a lead for deeper study.

  • Kenneth Harmon May 26, 2011, 1:01

    Question for All starting with Marc Millis, James Essig, and Ron S

    Given the statement by Ron S that FTL is simply time travel and nothing more and that if FTL is somehow achieved nothing can be known about what the traveler will do through given todays understand of GRT/SRT, is there general agreement with this observation? Einstein’s theories imply this, and I tend to believe this, but is the general consensus among you that this is indeed the case? I ask because years ago I read an article somewhere that indicated that if FTL was somehow achieved the Humans on the ship would actually age substantially faster then the people back home. I believe the article implied some form of Tachyon Drive as the notional propulsion system. The article also indicated that if Human Intelligence somehow was able to travel at the speed of light that for the light speed observer there would be no sense of past, present or future and instead everything would be occuring simultaneously ( “I am alpha, I am Omega, I am the beginning I am the end”, without being in any way meta-physical). Finally, the article speculated that in order to travel at Light Speed or FTL the entity would in all probability have to become something other then matter in its basic form and substance so the notion of Star Ships would be out for these entities.

    Perhaps, the most troubling implication of the Ron S statement is not whether or not FTL can be achieved. Instead, the ultimate irony would be if there was a “so what factor” attached to it. Obviously, it might be great fun to travel back and forth in time if this could be achieved, but it does not solve the problem of getting around even our local Interstellar Neighborhood in rapid fashion. As odd as this may sound there may be only a very small window of time within an Advanced Civilization’s development (assuming we are not alone) where an Advanced Civilization is “primitive” enough to require “Spaceships” to travel Interstellar distances. For example, if Ray Kurzweil’s projections for the 21st Century turn out to be in any way accurate it may be that the only time that Human/Machine Civilization is “primitive” enough to require Spaceships to travel Interstellar distances is in the 21st Century. By 2100 CE with 20,000 years of further development under our belt “Spaceships” may be seen as not much more advanced then Horse drawn Chariots. Of course I am very skeptical about all of this, but it is interesting to ponder some of the potential implications of the statement by Ron S. Perhaps, there really is a lot to what was portrayed back in 1968 in 2001 a Space Odyssey.

  • Rob Henry May 26, 2011, 1:18

    I think Byanus point trumps mine. I also agree that arguments of timing could have no purchase here. If our priority was important, then that would only lead us to contemplate the unlikelihood of us living at a time before FTL travel, when virtually all sentient beings who ever existed in our universe should exist after it.

    However I still feel that there is another possibility that is not vanishing unlikely in a statistical sense. If possessing the technology for some strange reason precludes individuals within it asking the question ‘what is the chance that I find myself part of a FTL technology civilisation’ this question is no longer valid after the event. Surely this must give a tiny bit of hope.

  • Tobias Holbrook May 26, 2011, 6:39

    “How can we be among the first civilizations in the universe and NOT be special? The principle of mediocrity would have us appear somewhere in the broad middle of all civilizations. ”
    Pah. The principal of mediocrity tells me that I’m not British, since Britons only make up 1% of the worlds population, so I should expect to find myself part of the other 99%.

    You can’t hold elevate the principal of mediocrity to a metaphysical level and make broad pronouncements based on it.

  • Anthony Mugan May 26, 2011, 10:54

    Regarding the discussion around if invention of FTL would prove we are alone, I would merely like to point out the ‘zoo hypothesis’ and related possible solutions to the Fermi paradox. If at some time in the future we invent FTL but decide not to interfere with other inetelligent but less advanced cultures, their subsequent discovery of FTL would not prove they were alone.
    The point simply does not follow logically. We would would have to see what we encountered.

  • Ron S May 26, 2011, 11:48

    Marc,

    The book you want is “Subtle is the Lord…”, which is Pais’ scientific biography of the man. More recently he wrote another one focused on his personal life. Pais had the advantage of knowing Einstein in his last years, being a physicist himself and having access to his papers after his death.

    Regarding the CMBR, that cannot be a reference frame. It’s just a soup of photons that fill the universe traveling in every which direction but with a black body energy distribution. It isn’t a thing and it isn’t anywhere in particular, and its parts are neither co-moving nor on non-null world lines. The photon sources may never have been causally connected, depending on your take on inflation. You will be hard pressed to come up with a cosmological scale structure that meets the necessary criteria. It’s probably impossible.

  • kurt9 May 26, 2011, 15:12

    The problem with arguments like the “zoo hypothesis” is that they assume that all individuals of the technological civilization act the same. That it, that every single person or group of people with access to a star ship would observe the protocol. I see no reason to believe that aliens would act in such a collective manner anymore than humans.

    There are three plausible explanations for the Fermi Question. One, they do not exist or are very far away, say, the Virgo Supercluster (this is what I think). The other is that something goes around killing sentient life whenever it shows up.

  • andy May 26, 2011, 16:41

    There was a recent paper on arXiv about the plausibility of the zoo hypothesis: Spatio-temporal Constraints on the Zoo Hypothesis, and the Breakdown of Total Hegemony

    Might be worth a look.

  • Greg May 26, 2011, 17:04

    What if an alien intelligence just can’t conceive of the physics or FTL travel itself? What if their brains are not based on neural nets, or computer “0 and 1’s”? What if they see via radio waves or sound waves or even mesons? their understanding of the physical world would be hard for us to conceptualize, all leading to an understanding of the universe far differently than we do.

  • Rob Henry May 26, 2011, 20:26

    Tobias Holbrook, you are correct in your doubts of some assumptions of mediocrity, but not for those that are rigorously backed up in a statistical sense. I think you will find that we are looking at the latter here.

    The correct statistical application of the principle of mediocrity is subtle. IFF we only knew of the existence of Britain and nothing else, we might legitimately use it to claim that at least 1% of the rest of the world was populated by humans. Under slightly different circumstances, we may somehow know that the rest of the world is peopled. This would now allow us to claim that probably at least 1% of the rest of the world had their own equivalents to “being British”. Now lets go further and say that anthropologists felt that they had proved that all humans felt national affinity. Then we could either claim that probably at least 1% of the rest of the world population lived in human nations that had at least 60 million, or that 1% of all human populations were in those of at most 60 million, even though we new nothing else of it.

    Such outcomes of the POM are very modest. Things only get interesting if we start to make claims that would have to bias the sample, such as what is the chance that a non-Briton will find themselves part of a nation that recently controlled a quarter of the worlds population. Such is the case for FTL travel.

    Perhaps the worse misuse of it ever was in “The Rare Earth Hypothesis”. Those of you who have not read “The Rare Earth”, might think I exaggerate. To you, their list of potential rare Earth factors that you will have heard, must have been given in the expectation that ONE of these will substantively provide the answer to intelligent life seeming to be so rare, and they give them all because we can not know which it is. You might point out to me that that approach does not really breach the principle of mediocrity, in the statistical context that science uses it, and you would be right. This is NOT the way that Brownlee and Ward approached it – they really do breach this fundamental principle of science as they openly admit.

  • Ron S May 26, 2011, 21:33

    Kenneth,

    I am at a loss about how to respond to you. Your comment contains a peculiar mix of fiction, supposition, “what if” questions about magical technologies. It’s sort of like the old cliche that if pigs had wings they’d fly. But how did the wings get there? What adaptive advantage did they give to pigs as they evolved to their present state? Since wings are appendages, to be consistent with its genetic heritage the winged pig would have to have only two feet, so a pig with wings and four feet stretches credulity. And so on into deeper ridiculousness.

    There are no tachyons, outracing a photon says nothing about your voyage duration or trajectory, and there can be no propulsion systems built on speculation. Do you see the relationship to winged pigs? Or, to try a different analogy, if we allow 1+1 to add up to 3, what does 1+2 add up to? How could we even begin to answer such a question? The problem is in the opening premise.

    There will almost certainly be new knowledge learned about how the universe works, and perhaps new or better-understood physical laws, but it’s a little soon to start writing the specification of the spacecraft that will exploit these advances. Yet until we have those specs we are hard-pressed to say what will happen when the start button is pressed.

  • Anthony Mugan May 27, 2011, 8:21

    I would be interested in seeing what the readership of this forum make of the conclusion to the paper by Duncan Forgan that andy references above, that I had just read myself, by coincidence. I was particularly thinking about it from the perspective of the experience likely to be had by an individual civilisation at around our stage of developmemt. There are of course many uncertainties in any such modelling, but my reading of it is that Forgan is suggesting that the original view of the zoo hypothesis – a dominant civilisation establishing a galactic hegemony, is statistically less likely, given our current understanding, than a series of local hegemonies. it thinking about this it would seem to me that the experience for one planet located at one point in space and time may be similar for all practical purposes as far as I can see, until, potentially, such local hegemonies themselves meet. The rules of the local hegemony would apply, unless the planet was lucky enough to be sufficiently far away to not be within the ‘sphere of influence’ of one of these local hegemonies at all. Would this be a fair interpretation of the data in people’s view?

  • Martin J Sallberg June 13, 2011, 8:58

    It is experimentally proven that spinning niobium supraconductors
    cooled by liquid helium affects gravity (ESA: Towardsa new test of
    general relativity, 2005). Several scientific theories, including string
    theory, also predict that gravity and electromagnetism unify in higher
    dimensions. It is possible that the Meisner-Meisner pressure forces the
    electromagnetic field out of normal spacetime. That makes it possible to
    make the gravitational effect much stronger by placing many spinning
    supraconductors close to each other. Another way to make the effect
    much stronger than in the ESA experiment is to conduct electricity
    through the supraconductors instead of relying on induction. Other,
    purely conjectural, possibilities include cooling high temperature
    supraconductors with liquid helium to make the effect extra strong, for
    who knows if it is the niobium itself that is crucial, or just the low
    temperature? It is worth an experiment anyway. But even without the
    third possibility, the first two, more well-founded possibilities can make
    the gravity-manipulating effect strong enough for practical use in space
    travel, make cheap launches possible, eliminate the need
    to carry propellant, and possibly even make Alcubierre drives and
    wormholes realistic. All well within our lifetime!

  • Martin J Sallberg June 14, 2011, 8:13

    “What if an alien intelligence just can’t conceive of the physics or FTL travel itself? What if their brains are not based on neural nets, or computer “0 and 1′s”? What if they see via radio waves or sound waves or even mesons? their understanding of the physical world would be hard for us to conceptualize, all leading to an understanding of the universe far differently than we do.”

    That overlooks the fact that intelligence IS the ability of PLASTIC (as opposed to hardwired) conceptualization. Computer 0 and 1s can never become intelligent regardless of their quantitative capacity because they can neither draw non-preconcieved conclusions from the accumulation of non-absolute statistical indications nor apply anything they know in different situations. Even the simplest insect is far smarter than even a hypotethical binary computer with infinite processing power would be. This shall patently NOT be confused with vitalism, because non-binary computers have been built, and they can solve problems otherwise reserved for living animals (on the other hand they must be trained and cannot be programmed like conventional computers). That shows that it is not being alive itself that is the key, but the scientifically measurable non-binaryness. There is animal groups with very different brain structures, sometimes separate origins of brains, but all use non-binary processing because Darwinian selection ensures that no binary brains are survivable. Paracites have learned to talk with humans as good as apes can use lexigrams, despite the fact that paracites have very different brain structures. It seems like it is the number of neurons that determines a continuous scale between mere conditioned learning and true language.

  • Ronald June 15, 2011, 10:40

    Martin J Sallberg:
    “It is experimentally proven that spinning niobium supraconductors cooled by liquid helium affects gravity”.
    “the (…) more well-founded possibilities can make the gravity-manipulating effect strong enough for practical use in space travel”.

    Do you possess full reference for these assertions? For this would be quite spectacular indeed.

    Another question: does the Mach principle/effect in any way relate to Heim’s theory?

  • Ronald June 16, 2011, 10:31

    Of all arguments above with regard to Fermi, I agree the most with Bynaus, also mentioned by kurt9: intelligent life and particularly advanced civilizations must be exceedingly rare.

    Why is that so hard to accept?

    Various recent guesstimates of the number of habitable planets in our MW galaxy vary roughly from 50 – 200 million. That may sound like a lot but it isn’t really. Not to come up with an advanced intelligence as a result. And even less so if you want two or more advanced civilizations overlapping in time.

    Abiogenesis may not be rare at all (funny, Interstellar Bill’s cosmic/geological argument for rarity actually indicates the opposite), life in the broadest sense may appear to be quite common, but most likely ‘we’ are extreemely rare.

    We may even be the only ones at this level in our whole MW galaxy at this moment, our nearest advanced-techno-neighbors being in the Andromeda galaxy, or even somewhere in the Virgo cluster, as kurt9 suggests.
    This may feel a bit lonely at first, but is not necessarily a bad thing: very few intelligent others to contest our place in the galactic pecking order. It may ultimately appear to be ‘our’ galaxy.

  • Ronald June 16, 2011, 10:42

    I know too little about this fascinating topic, but would FTL travel as a result of inertia/gravity manipulation really be time travel?
    I mean wouldn’t it imply that, either in a limited space or in another dimension, c would be increased (if gravity/inertia is reduced) and hence that SRT and causality would not be violated?
    Simply put, that the boundary would not be trespassed but shifted?