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Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com)
An anonymous reader quotes a report from Hacked: Earlier this month Hacked reported that a draft version of the much expected EmDrive paper by the NASA Eagleworks team, had been leaked. Now, the final version of the paper has been published. The NASA Eagleworks paper, titled "Measurement of Impulsive Thrust from a Closed Radio-Frequency Cavity in Vacuum," has been published online as an open access "article in advance" in the American Institute of Aeronautics and Astronautics (AIAA)'s Journal of Propulsion and Power, a prestigious peer-reviewed journal. The paper will appear in the December print issue of the journal. The final version of the paper is very similar to the leaked draft. In particular, the NASA scientists confirm the promising experimental results: "Thrust data from forward, reverse, and null suggested that the system was consistently performing at 1.2 +/- 0.1 mNkW, which was very close to the average impulsive performance measured in air. A number of error sources were considered and discussed." The scientists add that, though the test campaign was not focused on optimizing performance and was more an exercise in existence proof, it is still useful to put the observed thrust-to-power figure of 1.2 mN/kW in context. "[For] missions with very large delta-v requirements, having a propellant consumption rate of zero could offset the higher power requirements. The 1.2 mN/kW performance parameter is over two orders of magnitude higher than other forms of 'zero propellant' propulsion, such as light sails, laser propulsion, and photon rockets having thrust-to-power levels in the 3.33--6.67 uN/kW (or 0.0033--0.0067 mN/kW) range."
In other words, a modest thrust without having to carry fuel can be better, especially for long-distance space missions, than a higher thrust at the cost of having to carry bulky and heavy propellant reserves, and the EmDrive performs much better than the other "zero propellant" propulsion systems studied to date.
What's the usual format of an EM drive? Does it go on a satellite for maintaining orbit instead of a chemical thruster that'll one day run out of fuel? On an interplanetary probe for long-term acceleration, like solar sails might? How big should it be for useful propulsion, and what levels of power does it require -- given that heat dissipation is a perpetual issue for small spacecraft?
I've been following this for a year or so - very interesting. Over at Nasa Space Flight board there are a lot of people making these EM drives in their back yard, with varying results. A lot of this comes from the original work by Roger Shawyer. He has stated that he will show a drone running EM drive in 2017. If that works ...that would change everything. Cheap access to space would mean space-based solar arrays for terrestrial use. Here's an article about his patent.
There's also some very strange results with laser timing through an EM drive cavity. Almost like spacetime is being warped.
Just to put the numbers in perspective. A force of 1.2mN/kW is equivalent of a force of 0.12 gram.
A Tesla SP85 has a maximum effect of 350KW. This would (in theory) produce a force of roughly 40 grams, the weight of 10 sugar cubes.
A Nuclear submarine is able to produce an effect of 100MW, giving a theoretical force of 10kg.
A medium nuclear power plant is producing roughly 1000MW, and a force of 100kg.
Now, does it work? No idea, frankly. I'm more inclined to believe the results of, you know, an actual test than someone who didn't do the test but insists it can't work in spite of the test....
It's difficult to convey to a non-physicist just how accurately and consistently quantum field theory describes nature. Physicists routinely make calculations which have lower uncertainly than the best experiments. For example the anomalous magnetic moment (https://en.wikipedia.org/wiki/Anomalous_magnetic_dipole_moment) is in agreement with theory to ten significant figures.
Physicists tend to be fairly cautious describing results, but when it comes to basic theory at energies up to a few hundred GeV we are confident that we have *all* physical effects well and truly nailed. This doesn't mean that we can always solve the equations perfectly: quantum mechanics is hard, but the equations themselves are almost beyond reproach.
It's not undeserved hubris: it's trillions of independent experiments, billions of dollars and hundreds of thousands of man-years working on the theory by lots of very smart people. The theory, quantum field theory (QFT), is simple, consistent and universal. It describes everything we can see around us, with the exception of gravity.
If you ask an actual physicist what he or she thinks of the EM drive, they will overwhelmingly say that is is highly likely there is an unresolved source of error because violation of moment conservation has never been observed and is inconsistent with QFT.
Yes, yes it does so appear. The "math" is astoundingly simple: No matter how you state it (N's laws, in terms of Lagrangians or Hamiltonians or Stokes vectors or Grassmannian objects, and whether you use a classical or quantum mechanical basis), 4-momentum is expected to be conserved, and conserved locally. Either that deep, deep principle is wrong, in which case a gigantic new set of possibilities opens up (despite the principle appearing to work for every other observation and experiment thus far); or not every avenue of momentum transfer has been properly quantified in the EM Drive experiment.
My money, and the money of every other physicist I know, is on the latter.
Bearing in mind that all this is just a fun exercise, and there's no reason to believe that the 1.2 mN/kW thrust will scale to megawatts of power, here's how long it would take to get to Mars if this finding scales to a practical spaceship drive:
foo mane padme hum
which suggests a position accuracy of ~1nm which is less than the size of an atom
Might want to double check that, I'm pretty sure atomic radii are measured in picometers.
Your entire post is nonsense. You're "not even wrong".
Socialism: a lie told by totalitarians and believed by fools.