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According to physicist Harold White, leader of the NASA Eagleworks team, it can't simply be a "photon rocket": The NASASpaceflight.com group has given consider

• InclinedPlane 11y ago
  Realize that this is the exact same level of verification as superliminal neutrinos, except at a vastly decreased level of rigor. At this point the overwhelmingly likely explanation is that there is some phenomenon at work which we don't understand or haven't properly accounted for, not that there is new physics afoot.
  • lotsofmangos 11y ago
    From a Bayesian perspective, it isn't. One experiment that is difficult to disprove does not carry the same weight as 5 different ones giving similar results.
  • jcoffland 11y ago
    Really what's the difference. Either we can fit it in to our models or we have to change the models. It always bothers me that so many people in the scientific community speak of our scientific models of the physical world as if they were truth itself. All models are flawed and only imitate reality by definition. We must accept that our models are only a glimpse of the real thing. We barely manage to grok our own planet let alone galaxies unfathomably beyond our reach yet we are consistently surprised when our models turn out to yet again be wrong. We know for a fact that our currently accepted physical models are flawed. To start with, we cannot fully reconcile gravity or "spooky action at a distance." The only reason our current models are useful, like any useful model, is that they are somewhat good at predicting a very limited set of future outcomes given measurable parameters. Why can't we admit that what we currently know only seems impressive to a few moderately advanced apes but in reality it is likely only tiny drop in the bucket compared to the knowledge our universe holds. All that said I'm very pro skepticism. Just because science is dumb does not mean every other random idea is valid. It's the common arogance of the scientific community that grates on my nerves. End rant.
    • tjradcliffe 11y ago
      > Why can't we admit that what we currently know only seems impressive to a few moderately advanced apes but in reality it is likely only tiny drop in the bucket compared to the knowledge our universe holds. Because that would be to deny without any reason but empty speculation that what a small group of scientists have done in the past 300 years is a singularly impressive achievement, adding more to human understanding of the universe than far large groups have done over far longer spans of time. People don't know very much aren't impressed by what the discipline of publicly testing ideas by systematic observation, controlled experiment, and Bayesian inference has taught us about the world, and they radically under-estimate how much we know, instead comparing the vast and wonderous extent of our actual knowlege with their own fantasies of what might be known one day. I look back at the science of the 1800's and I'm impressed by how much they knew, how much they did. I expect scientists a century or two from now will look back and think the same of us, while the ignorant people of their day will dismiss the thoughts and judgements of scientists of that time as nothing much compared to the fantasies of the ignorant.
• Steuard 11y ago
  Yes, sure, they've measured something surprising. I have no reason to doubt that. A few years ago, the enormously more respected folks at the OPERA experiment were willing to announce that they had seemingly detected neutrinos moving faster than light. Despite this coming from a large group of scientists with top-notch credentials, that was immediately doubted by almost the entire physics community, and sure enough, the observed effect turned out to have been caused by a bad cable connection. If anything, conservation of momentum is more deeply embedded in the structure of known physical principles than the speed of light limit. And this little group within NASA doesn't have remotely the level of credibility that OPERA had. So it's even easier for me to believe that this measurement is due to some loose cable or improper calibration or failure to isolate the test environment, too.
  • ngoldbaum 11y ago
    This reminds me of the story behind the "discovery" of cold fusion in the 80s. Sure, Pons & Fleischman may have thought they measured something, but in the end the whole effect could be attributed to careless experimental design and procedure. See this paper: http://pus.sagepub.com/content/5/2/121.short http://pus.sagepub.com/content/5/2/121.short (unfortunately behind a paywall)
    • tzs 11y ago
      Cold fusion is a bit more complicated than that. The early experiments were certainly flawed, and there were way to many people announcing results for publicity before they had checked their work. After a few years, it was no longer socially acceptable for respected scientists to work on cold fusion. It didn't matter anymore how good your reputation was as a researcher, or how carefully designed your experiment was--if your research was in cold fusion, it would get largely ignored. Unfortunately, this happened around the time a couple groups of respected researchers with good experiment design were getting interesting results pointing to real new phenomena, and perhaps explaining why prior results had been so erratic. David Goodstein around this time wrote a great article [1] looking back at cold fusion, which included a discussion of these later results, and how socially science had reached a state where they could not be considered. Here are the last few paragraphs. All of this was much less important than the fact that Cold Fusion experiments, if they gave positive results at all, gave them only sporadically and unpredictably. When Bednorz and Mueller announced the discovery of high-temperature superconductivity in 1986, no one carped about control experiments, because, once the recipe was known, any competent scientist could make a sample and test it and it would work immediately. If, at their press conference, Pons and Fleischmann had given a dependable recipe for producing excess heat, they very likely would be Nobel Prizewinners now (as Bednorz and Mueller are) rather than social outcasts from the community of scientists. The essential key to the return of Cold Fusion to scientific respectability is to find the missing ingredient that would make the recipe work every time. Experiments done in the U.S. and in Japan, and reported at the Maui meeting indicate that the missing ingredient may have been found. In all the various Cold Fusion experiments, the first step is to load deuterium into the body of metallic palladium. The issue is how much deuterium gets into the metal. The ratio of the number of atoms of deuterium in the metal to the number of atoms of palladium is called x. It turns out, by means of electrolysis, or by putting the metal in deuterium gas, that it is rather easy to get x up to the range of about 0.6 or 0.7. That is already a startlingly high figure. If there are almost as many deuterium atoms as palladium atoms in the material, the density of deuterium (a form of hydrogen) is essentially equal to that of liquid hydrogen rocket fuel, which can ordinarily exist only at extreme low temperatures. In other words, palladium (and certain other metals including titanium) soak up almost unbelievable amounts of hydrogen or deuterium if given the chance. This is far from a new discovery. However, according to the experiments reported at Maui, x=0.6 or 0.7 is not enough to produce Cold Fusion. Both the American and Japanese groups showed data indicating there is a sharp threshold at x=0.85. Below that value (which can only be reached with great difficulty and under favorable circumstances) excess heat is never observed. But, once x gets above that value, excess heat is essentially always observed, according to the reports presented at Maui, and recounted by Franco Scaramuzzi in his seminar at the University of Rome. The audience at Rome, certainly the senior professors who were present, listened politely, but they did not hear what Franco was saying (that much became clear from the questions that were asked at the end of the seminar, and comments that were made afterward). If they went away with any lasting impression at all, it was just the sad realization that a fine scientist like Franco had not yet given up his obsession with Cold Fusion. They cannot be blamed. Any other audience of mainstream scientists would have reacted exactly the same way. If Cold Fusion ever gains back the scientific respectability that was squandered in March and April of 1989, it will be the result of a long, difficult battle that has barely begun. Recently, I told this story in a Philosophy course we teach at Caltech called "Ethics of Research." The first question, when I finished my tale, was, do I believe in Cold Fusion? The answer is, no. Certainly, I believe quite firmly the theoretical arguments that say Cold Fusion is impossible. On the other hand, however, I believe equally firmly in the integrity and competence of Franco Scaramuzzi and his group of co-workers at Frascati. I was disturbed when I saw that Franco had gotten caught in the web of science-by-news conference in April 1989 (although I was truly pleased that he finally got the long overdue recognition his agency ENEA owed him), and I was even more distressed when I learned that Franco and his group had observed excess heat (the "bad kind" of Cold Fusion). However, I have looked at their cells, and looked at their data, and it's all pretty impressive. The Japanese experiment showing that heat nearly always results when x is greater than 0.85 looks even more impressive on paper. It seems a particularly elegant, well designed experiment, at least to the untutored eye of a physicist (what do I know about electrochemistry?) What all these experiments really need is critical examination by accomplished rivals intent on proving them wrong. That is part of the normal functioning of science. Unfortunately, in this area, science is not functioning normally. There is nobody out there listening. I suppose that, if nuclear fusion really does take place whenever x is greater than 0.85 in palladium, the world of conventional science will eventually be forced to take notice. If not, then the whole story I have told you is nothing but a curious footnote to a bizarre and ugly episode in the history of science. Either way, I think the story illuminates the inner dynamics of the scientific enterprise in a way that few other stories have done. For that reason alone, it may be worth telling. [1] http://www.its.caltech.edu/~dg/fusion_art.html http://www.its.caltech.edu/~dg/fusion_art.html