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Leaked NASA Paper Suggests The 'Impossible' EM Drive Really Does Work (sciencealert.com)
A source close to NASA Eagleworks has leaked the test results of the 'impossible' EM Drive. While it's important to note that the results that have been leaked haven't been published in an academic journal, they do suggest that the system works and is capable of generating force of 1.2 millinewtons per kilowatt in a vacuum. ScienceAlert reports: The paper concludes that, after error measurements have been accounted for, the EM Drive generates force of 1.2 millinewtons per kilowatt in a vacuum. That's not an insignificant amount -- to put it into perspective, the super-powerful Hall thruster generates force of 60 millinewtons per kilowatt, an order of magnitude more than the EM Drive. But the Hall thruster uses fuel and requires a spacecraft to carry heavy propellants, and that extra weight could offset the higher thrust, the NASA Eagleworks team conclude in the paper. Light sails on the other hand, which are currently the most popular form of zero-propellant propulsion, use beams of sunlight to propel them forward rather than fuel. And they only generate force up to 6.67 micronewtons per kilowatt - two orders of magnitude less than NASA's EM Drive, says the paper. The NASA Eagleworks team measured the EM Drive's force using a low thrust pendulum at the Johnson Space Centre, and the tests were performed at 40, 60, and 80 watts. They were looking for any sign that the thrust could be a result of another anomaly in the system, but for now, that doesn't appear to be the case. "The test campaign included a null thrust test effort to identify any mundane sources of impulsive thrust, however none were identified," the team, led by Harold White, concluded in the paper. "Thrust data from forward, reverse, and null suggests that the system is consistently performing with a thrust to power ratio of 1.2 +/- 0.1 millinewtons per kilowatt." But the team does acknowledge that more research is needed to eliminate the possibility that thermal expansion could be somehow skewing the results. They also make it clear that this testing wasn't designed to optimize the thrust of the EM Drive, but simply to test whether it worked, so further tweaking could make the propulsion system more efficient and powerful.
Ran some numbers. Assuming the power generator and thruster itself has zero mass (obviously not, but it lets us set an upper limit), the energy available in 1kg of U235, at 1.2 millinewtons/kw, would accelerate that 1 kg mass to about 0.35 C, over the course of about 1000 days.
Add in mass of ship, generators and thrusters and you're looking at considerably less acceleration and top speed, but if this thing works at all (a big IF, granted), manned starships are just within the range of possibility. It'd still be a multi-year (probably multi-decade) trip, but hey.
Really dude. You have such a hard on for Trump that even when we finally get to read something interesting that doesn't involve politics you have to try and bring politics into it anyway.
Eagleworks is NASA's "check weird shit and see if its real" department, so they are exactly the place to check this.
How is this any different from "magical force that synchronizes photons across space and time.... but only if I pre-filter the results of my experiments before shoving them into my statistical test"?
Higher physics is absolutely full of magic pseudo science shit, and this might be something real and simple, that just isn't understood by the current bogus nature of magic fluffy physics.
If you use 1 kW to generate photons and use them as your rocket exhaust, then you produce (1 kilowatt / speed of light) = 0.00334 millinewtons. This EM drive produces 360 times more thrust, so it can't be explained that way.
Here's a link to the NASA paper on the apparently successful test: https://drive.google.com/file/...
And here is a presentation by the technology's inventor, Roger Shawyer https://vimeo.com/channels/Emd...
Warning: Shawyer may well be brilliant, but he is the Anti-Musk in terms of his presenting and motivational skills. This guy could seriously announce a working warp drive in a way that would make people walk out of the presentation half way through. If he has funding problems, he needs to get someone else to present his technology and business case for him.
Where are we going and why are we in a handbasket?
Warning: Shawyer may well be brilliant,
Nope. He first "derived" it using relativity and then ran with the result. It was obvious to just about every physicist ever that the result MUST have been bogus because relativity probably conserves momentum. The thing is, that's a mathematical proof so it holds always, no matter how clever your shape, how many springs or magnets you have or how smart you seem to be.
It is literally impossible to have a reactionless thruster while constrained by the bounds of relativity. This is well known and thoroughly proven and is basic undergrad level physics, yet was apparently unknown to Shawyer.
Not only that, he wouldn't even accept the result (i.e. Noether's theorem) until someone found the actual error in his working. It wa eventually found.
Not a great start for brilliance.
SJW n. One who posts facts.
Second, everyone that does speculate about it agrees that to probe the existence of this discretization would require particle collisions with energy around the Planck energy, about 10^28 eV.
That's a rather strong statement considering that there are groups on ATLAS and CMS looking for evidence of Large Extra Dimensions which would reduce the energy scale for this to a few tens of TeV. Personally I don't think they will find anything but certainly they are clearly speculating about it at far lower energy scales.
To think that some lame tabletop experiment using only classical electrodynamics, running at most at 80 watts, somehow magically found a way to probe phenomena from an energy scale 15 orders of magnitude larger than the LHC scale, just shows a complete lack of knowledge of all the science involved.
Unfortunately again this is not really a correct thing to say because there are such experiments hunting for axion models of Dark Matter. The LHC is one way to get at high energy physics that is almost guaranteed to find new physics in our energy reach so it is worth the huge cost. However this does not rule out others trying lower budget approaches which can afford to be riskier and to only probe certain models. It is worth remembering that only a few years ago the Nobel prize was awarded to a group which essentially used scotch tape to separate graphite layers something which far more expensive approaches had failed to do.
You are a perfect example of the anti-intellectualism that is destroying the UK. Literally destroying it, as Scotland and maybe Gibraltar look likely to leave the union in some fashion.
I hope you enjoyed seeing men-of-the-people like Boris Johnson and Michael Gove, both of whom went to Eton and are millionaires, win that referendum. Especially now our future looks bleak, the Pound has crashed and continues to fall, and bigots have been emboldened by what they perceive as support.
Of course, in reality only about 18% of eligible voters voted to leave...
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SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
As the indefinite production of energy is impossible,
No shit!
EM drive does not produce energy then it is not a perpetual motion machine
Yes it is, and that's the problem.
It produces a force given power in. That means it will produce a constant acceleration at a constant power. But kinetic energy grows quadratically with speed.
Once you get fast enough, the energy growth (i.e. power) due to increasing k.e. outstrips the constant power pumped into the system. At that point you'd be getting energy from nowhere.
And that is why the EM drive is a perpetual motion machine.
The only way of making it "work" is more extreme changes to physics. If the power drops with speed, that means speed is not relative, the aether pretty much exists (despite the many failed attempts to find it) and time dilation doesn't work properly so GPS doesn't work. Both me and my phone (and my two previous phones) are very much of the opinion that GPS does in fact work.
SJW n. One who posts facts.
If it has mass, how can it travel at c?
It doesn't, but not for that reason.
A simplified answer is that because it travels at c, spacetime doesn't apply to it, only to what it passes through. c is an asymptote, which other particles can only approach. Photons live inside the asymptote, and are not subject to the standard rules for what occurs.
In E=mc^2 (or the general expanded version), "c" is a constant for distance divided by time. As Einstein discovered, time itself is suspect - it varies. Which is fine as long as you only approach c, because distance compensates exactly. But when time no longer approaches zero but is zero, "c" becomes infinity divided by zero, which is meaningless. A single photon is then everywhere, anywhen, which doesn't match our observations.
We can only assign a photon "mass" through equivalence - what mass changes occur when a photon is created or destroyed. While[*] it exists, it's meaningless to assign it mass, but it's meaningful to assign it a mass change potential, or momentum.
[*]: Also a meaningless term for a photon, as a photon's life span is instantaneous or infinite, never anything in-between. Any "while" only affects the surroundings, not the photon itself. It laughs at clocks.
If you have enough delta v you can fly on a hyperbolic orbit, which can be as fast as you like. That dv can be delivered all at once, at the beginning (and hopefully the end) like we do it now, or it can be delivered continuously, like we'd do with this engine.
"for all we know we live in the aether and the device materializes invisible paddles to row it."
We do live in the aether. The qualitative description of modern quantum field theory is pretty much indistinguishable from qualitative descriptions of some aether theories. Relativity suggests that you can't paddle through the aether, but one of the theories for how this thing works is essentially that.
If Eagleworks has conclusive data that the EmDrive does indeed work, then there should be a Manhattan Project level of funding pushed towards it. It would change everything.