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No, NASA Did Not Accidentally Invent Warp Drive
StartsWithABang writes: As Slashdot has previously reported, NASA Spaceflight has claimed to have vetted the EM Drive in a vacuum, and found there is still an anomalous thrust/acceleration on the order of 50 microNewtons for the device. While some are claiming this means things like warp drive and 70-day-trips-to-Mars are right on the horizon, it's important to view this from a scientist's point of view. Here's what it will take to turn this from a speculative claim into a robust one.
This is actually the conflation of two different stories.
The first thing to understand is both stories are coming out of the group at NASA whose job it is to deal with the crackpot theories that might not quite be false.
One group is working on a warp drive that while theoretically possible, even the person that invented it doesn't think it can be built. They are working on the very first step. Their detector for when they have completed the first step just went off. So now there is a chance they have completed the first step, which is more than anyone thought they would. Or their detector could have just gone off accidentally. AFAIK, they have not said any more about the event, but I 'm not actually following it. I don't believe they have made any claims other than their hardware detected a signal.
Separately, there have been several labs working on the EM drive that all have positive results. Including one lab in China that use a large amount of power and claims a large amount of thrust. Up until now, everyone has been saying the thrust is coming from thermal convection of the surrounding air.
The current experiment attempts to test that theory and seems to say that it's not thermal convection. So NASA has just eliminated one possible explanation of what is going on. They have not concluded the EM drive works or that the thrust is not coming from a known law of physics. Their actual conclusion was that the EM drive was intriguing and more experimentation should be done to try to find out what is really going on.
All the claims of Mars just being a quick jaunt away come from people on a public message board speculating on what it would mean if the EM drive actually works. They are not coming out of NASA.
I did see one claim that someone at NASA had written a computer simulation that assumed some obscure aspect of Quantum theory was wrong and that said model predicted the results of all three experiments and that it also explained why NASA initially had trouble measuring the thrust from their drive. I believe that claim is dubious however.
The real take away from all this is that perhaps the EM drive isn't 100% bunk, but maybe it is. The jury is still out. I wouldn't recommend funding any of the kickstarter projects that want to build an EM drive.
The energy of the thrust effect is basically lost in the measurement error. Hell, the device measuring it could be affecting the measured thrust.
That's not true. They're measuring 30-50 micronewtons on a device with a 10-15 micronewton margin of error. Do you seriously think that the NASA scientists who did the testing don't grasp how margin of error works?
The people at NASA have been doing this with a very small budget since this whole thing is still within crackpot territory. They have only been able to use equipment which can operate / measure over small ranges, so that's what they've been doing. They hope to eventually have other labs with better equipment will test at even greater powers (after getting above 100 micronewtons, they plan to have Glenn Research Center, Jet Propulsion Lab, and John Hopkins University Applied Physics Lab take over).
There's a nice thread on Reddit summarizing what we know so far.
It's a thing that appears to produce thrust by unknown means. That's all. It's very interesting, but it has nothing to do with anything that anyone would call a warp drive.
One point to add here: it definitely isn't a warp drive, but the guy that invented it in his garage did so while following a theory he had that the relativistic effects at the moment an electromagnetic wave is reflected can be harnessed to turn the energy of those waves directly into thrust. There is a very simple test nobody has done yet (that the inventor himself is still trying to save money to do, last I heard) - that is to replace the copper resonating cavity with a superconducting cavity to drive up the Q-value. If his theory holds true a 1000W magnetron from a microwave oven will be able to lift a small car off the ground in that setup.
Because they used their warp-field interferometer and found that the results possibly showed that the inside was bigger than the outside. You can find more info on it on the NASA forums. http://forum.nasaspaceflight.com/index.php?topic=36313.1860
The designs were different. The power sources were quite a bit different. Read up.
If th devices are different then they can't be used for verification of results.
DERP.
No-one - that is to say, no-one with an ounce of scientific credibility - is claiming it's a warp drive. There's no reason to even start to consider the idea that it might be a warp drive.
Oopsie.
Red to red, black to black. Switch it on, but stand well back.
No. These tests prove that the device is real, and that it produces force.
Actually that is NOT what these tests show. They show that someone has done an experiment which, using their apparatus, returns readings consistent with a micro-newton force. What the experiment has NOT shown is that this is due to some new, as yet unexplained, physics.
There are a myriad of other, far more mundane, possibilities to generate such results before anyone will seriously start believing in new physics as an explanation. For example did they account for the radiation emitted bouncing back and forth between the apparatus and the vacuum chamber walls?
After the results have been confirmed independently and all the possibilities people can come up with disproven then you have an interesting result which is unexplained. At this point there are still two possibilities: either new physics OR an effect so subtle that nobody has thought of it. The only way to prove new physics is therefore to come up with a theoretical explanation which allows testing.
Whether or not you agree with this this is how science works: there are simply too many ways that a precision experiment like this can be fooled and history is littered with examples of this happening e.g. faster than light neutrinos, gravitational waves in the cosmic microwave background, cold fusion etc. The results have to be confirmed and stand several years of scrutiny before people will start to believe that they are interesting. Even when that happens to get people convinced that there is new physics here you need a model for that new physics that makes predictions which can be confirmed.