4 ms·

For all those saying this is impossible because of X, I think the great Richard Feynman put it best: "If it disagrees with experiment, it's wrong" https://www

• bcoates 12y ago
  Of course, but there's still a lot of things consistent with the experiment that are less improbable than reactionless thrust. This is still an important experiment, though -- if your testing methods are discovering 'impossible' effects, they are discovering effects that are possible but wrong, too. This is something worth getting to the bottom of. Every contradiction is a discovery, even if it's not the discovery you want.
• ceejayoz 12y ago
  Assuming you can perfectly rule out measurement, experimental design, etc. flaws, of course.
• Steuard 12y ago
  Experiments this delicate are very difficult to get right. And it is very difficult to overstate just how much established physics would have to be scrapped if momentum conservation turned out to be violated. (Just for starters, relativity implies that non-conservation of momentum in one frame must always involve non-conservation of energy in another.) Why would quantum field theory calculations match experiment to ~12 digits of accuracy if its basic foundations were flawed? (Those calculations are affected by literally every possible quantum vacuum effect, so why wouldn't introducing some new set of momentum violating interactions completely throw off the results?) This is an astoundingly extraordinary claim, and it should thus require tremendously compelling evidence. I'm not at all convinced that these experiments are clean enough or consistent enough to even approach that standard.
• anon4 12y ago
  Isn't this drive using relativistic effects similar to what allows a magnet falling down an aluminium tube to produce an opposite magnetic field and slow down? I mean, clasically speaking that effect is also impossible.
• aetherson 12y ago
  You want to apply Bayesian reasoning to this. Conservation of momentum is a very well-tested, long-established physical law. Our priors going into this experiment should be "it is impossible to produce thrust without throwing mass or energy out the back of your thruster!" at something like 99.99999% So now this experiment has happened! That should indeed reduce our belief in the above. But there are other explanations, like, "the experimenters screwed up." So previously our beliefs were: There is no way to get thrust without blowing mass or energy out the back end of a thruster (and if you do it as energy, it's a completely enormous ridiculous amount of energy): 99.99999% There is a free lunch: 0.00001% Now we think: There is no way to get thrust without blowing mass or energy out the back end of a thruster (and if you do it as energy, it's a completely enormous ridiculous amount of energy) (and those experimenters screwed up): 99.99998% There is a free lunch: 0.00002%
• dragonwriter 12y ago
  > "If it disagrees with experiment, it's wrong" Sure. But if a small number of easy-to-misconfigure experiments appear to disagree with the conclusion of a large number of experiments of various difficulty all pointing in the same direction, its not unreasonable to suspect that the most likely explanation is an error in the setup or interpretation of the small number of experiments.