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Why the "NASA Tested Space Drive" Is Bad Science
StartsWithABang writes Just over a century ago, N rays were detected by over a hundred researchers and discussed in some three hundred publications, yet there were serious experimental flaws and experimenter biases that were exposed over time. Fast forward to last week, and NASA Tests Microwave Space Drive is front page news. But a quick analysis shows that it isn't theorists who'll need to struggle to explain this phenomenon, but rather the shoddy experimentalists who are making the exact same "bad science" mistakes all over again.
Have they accounted for the presence of skeptics during the experiments? That is likely the cause of any anomalies.
The NASA science is just fine: http://www.wired.co.uk/news/archive/2014-08/07/10-qs-about-nasa-impossible-drive
The result from NASA may or may not be real. However, this refutation is bad science writing and bad science.
There are two glaring errors in it:
Apart from these two actual errors in description, the only "evidence" the author has is "This looks sort of similar to cases where science has gone wrong in the past".
That *is* clearly a warning sign, but it is not actually sufficient to say "This is wrong".
Any good science student should be aware that our understanding of physics changes over time. Clearly this device is unlikely because it requires a change to the "laws" of physics.
The article explains why any good scientist should be able to laugh this off based on the reported experimental results.
The real "Libtards" are the Libertarians!
Wait, is this guy talking about space drives or global warming skeptics?
FTA:
1. The magnitude of these effects varied tremendously from experiment to experiment. //endtroll
2. The threshold of measurement—the difference between a detection and a non-detection—was always extremely close to the actual claimed detection.
3. Many attempts at confirming the experiments by some of the leading scientists of the day, including Lord Kelvin, Heinrich Rubens and Robert Wood, all produced null results.
4. And finally, even if you restricted your data sets to the positive the experimental results, their claims were inconsistent with one another.
FTFY
Just because you can't prove global warming is happening doesn't mean that it isn't. The science behind it is settled since over 90% of the scientists voted that it is happening. You can't disagree with it without being anti-science because of that.
25 years ago there was desktop cold fusion. A lot of people wanted it, there were conferences on it, probably at least a hundred million was invested in it over a year or two. but it was bogus. The hypothesis was sound, it was no completely unreasonable, but the experiments showing a positive results on the hypothesis were flawed. It is not that cold fusion does not exist as something that might happen, it is that we have not shown it happens. I don't want to muddle the situation, but there is a clear line between what can happen and does happen in the lab. Theoretical people have told me that their models are necessarily not connected with reality. They are math, and the math sometimes tells us what is going on, sometimes fools us, and sometimes is just bonkers. What differentiates all this is good experimental science, which is really hard to do. I mean really hard, and for the most part does not lead to a theory, but only data that can be collected by math. This is why even though Galileo did a lot of good research, it was 100 years before the math caught up and we were able to do what we now classify as as science.It is why electromagnetic, the speed of light, quantum mechanics, and what is to follow is going to drop out the math. Which is to say we have a very complex interactions. Virtual particles drop out the math. The math says that they must exist, but inherently can't do anything useful. This is in the same way that photons can be coupled so they may seem to act faster than the speed of light(maybe, until we get distances longer than the earth-moon system we cannot really know) but no one expects information to be communicated faster than the speed of light. The end result is that if you have an experiment that violates the math, you have to be very sure it is a good experiment, and the consensus is quickly building that this is not. There is a certain responsibility to being an experimentalist. One can't just willy nilly say there are 40 dimensions of energy is created from the aether. On can be sloppy with conclusions, as Einstein was with the photoelectric effect, or Milikin in his oil drop experiment, but one does have a responsibility to do ones best to control systematic errors, and not jump to conclusions when one does not fully understand those errors. Unless, of course, like the two cited authors you are lucky enough to be accidentally correct.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
I thought that this take was pretty appropriate when all we had to go on was the conference abstract. Now, however, the full paper (still not peer reviewed) is out, and it is much better. I still think it is wrong, but I do not think it is bad science, and it will have to be refuted experimentally.
Comments
* the "null thruster" is something of a red herring from the abstract. Reading the paper, they have a true "null load," which shows no thrust, while the "null thruster" was a mod of a Cannae drive, and so more of a test of drive theory than the experimental setup, and, in any event, they tested several types of drives.
* they did pretty much all of the things you would like to see (such as reversing the direction and making sure the thrust reverses).
* they seem to have done a thoughtful and careful job, including testing in vacuum.
So, I still think they are likely wrong, but this ups the ante. In my opinion, you can't just say "this is obviously wrong." I bet there will be a bunch of attempts to replicate it in labs all over the place.
I find the theories here (and I have now read several in some depth) to be bad, either wrong, or handwavy, or both*. I would discount them entirely. In the unlikely event that this effect is real (and I mean, some non-standard physics effect), then the theory is likely to be something different than any of the proposals, The experiment's the thing, and the game now has to be disproving the Eagleworks results. Only once a bunch of people have failed to do that (or one person has done it) is there much else to say.
* On pushing on virtual particles or quantum spacetime or whatever. These are 1 GHz photons, more or less. Such pushing would cause a _vacuum_ dispersion. Vacuum dispersion limits are set by timing of high energy photons from Gamma ray bursts across cosmic distances. These tests use ~ 100 MeV photons over ~10^10 light years, and so are many orders of magnitude tighter than the NASA Eagleworks results. This in my opinion rules out any photon - vacuum interaction as the cause of these anomalous thrusts.
Sorry. Science doesn't work by votes.
It's the reporting. This wasn't a peer reviewed scientific discovery, and it didn't claim to be. It was just a paper that laid out how the experiment was done, and what the results were, nothing more. Just because IFL Science, like every other tech/science site, picks up the story and hints at trips to Mars in a matter of weeks, doesn't mean that's what the experimenters were claiming.
This is how science works. You do experiments, you post your methods and results. Other scientists may do the same. If there is enough evidence that something may be at work, you do more. If you end up showing that everything we thought we knew about the universe was wrong, THEN YOU START CHANGING THE TEXTBOOKS.
The law of conservation of momentum, like all scientific laws, comes with the caveat that our understanding of how the universe works is correct. They are not immutable. Given reproduceability, predictability, and strong empirical evidence, it probably is correct; but that doesn't mean it may not need "tweaking" in the face of new evidence. It could also be that no scientific principles are being broken here, it's just there's something else at play we don't understand.
People who claim otherwise are really just religious zealots in a lab coat.
I'm sorry, but your opinion seems to be wrong.
What does that even mean? The Chinese reported some result, NASA tried to reproduce it, and didn't get very convincing results. Any halfway reasonable person looks at what was reported in the press and says "hey, nothing really to see here, they didn't really prove or disprove anything", to which one might add "how nice that people try some new and crazy stuff occasionally".
Which part of that chain of events is supposed to constitute "bad science"? Who exactly is supposed to have been fooled? Which step along the way does Siegel consider "bad science" and why?
Instead of making a rational argument for the cost/benefit of this particular experiment, Siegel goes off on some tangent about N-rays, supposedly illustrating the foolishness of some experiments. But there are many other cases where weird observations and experiments that most people thought never could work opened up entirely new areas in physics and biology. If one can learn anything from the history of science, it's that you should sometimes try crazy and foolish experiments because occasionally, they yield a big payoff.
Nobody knows whether reactionless drives are "impossible" or not; anybody who makes definitive statements one way or the other is a charlatan at this point, including Siegel.
The known laws of physics violate the known laws of physics, because they are not only incomplete but internally inconsistent. Somewhere along the line, you will have to do experiments whose results might violate the known laws of physics if you want to make progress.
I still don't know what that "this" is that Siegel is referring to. How do you know that the results aren't reproducible or robust if you don't try to reproduce them?
Siegel has the kind of dull mind that we don't want to teach our next generation of scientists or kids, and it is disturbing that guys like him are actually active in science education. Kids: try stupid things that violate known physics. Try things that sticks-in-the-mud like Siegel tell you don't work. And try to reproduce other people's experiments, both the ones that everybody believes and the ones nobody else could get to work.
No, it is perfectly possible (and well understood) that you can produce thrust using pure energy with no mass. Just put a lightbulb and a reflector on your ship; as long as you can power the lightbulb you will produce thrust. The problem with this is that it is ridiculously inefficient, and since your power generation is not massless, this is roughly equivalent to using pathetically bad fuel.
Also, don't confuse energy and momentum. They are separate things, and both are conserved independently of each other.
The trick to making a good spaceship engine is converting energy efficiently into ship momentum. As far as we know this means creating high-momentum exhaust; conservation of momentum then means your ship gains momentum in the opposite direction. However, the problem is that to create high-momentum exhaust you either need high mass (and this means your ship carries, and has to accelerate, tones of fuel), or you create high-velocity exhaust (which due to the kinetic energy formula means you use a lot more energy).
If you could find a way to skip the whole exhaust thing and transfer momentum directly into something not on your ship, you would have a space engine far superior to any we know of. The idea with this research was to transfer it into the quantum vacuum something-or-other. This would be analogous to how an airplane transfers momentum to the atmosphere or a boat to the water or a car to the land. In theory this could work and even be more efficient than using light as your exhaust.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
You are mistaken. Energy is converted to waste heat (which is a form of energy, so total energy is unchanged). Momentum is unchanged - some of it is simply transferred to Earth.
Conservation of momentum is just as fundamental a principle as conservation of energy. That doesn't mean that a drive that requires no fuel is impossible - because you can convert energy to matter - it just means that it has to dump the counterforce somewhere to keep momentum accounts balanced.
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
It's sad how pathetic the pretenders on Slashdot are sometimes. So full of themselves and sure that they are smarter than the next guy.
I know it's appeal to authority, but NASA doesn't employ idiots. And if you had bothered to do even a simply Google search you would have found this which sheds some more light on the situation.
Just to save you the effort, the abstract sucks (most likely written by a public relations flunky), they were very careful in setting up the experiment, it WAS done in a vacuum, there is something there. Note that they didn't explain it, they just report their observations.
But you go ahead and stick with your second year physics student attitude.
Oh for fuck's sake... Time to debunk this shit, again.
TFA got it wrong as well, so I suppose I can't blame you people for getting it wrong too, but please try doing a little more research?
A little background: The EmDrive was invented by a guy named Shawyer. It was tested by NASA, among others, and found to produce about 91 microNewtons. (I'll address the 30-50 that TFA talks about too.) That's way less than the Chinese found, but NASA was also testing it at much lower power and say they are planning to test a higher-power version.
The article mentions "... and a third person, Guido Fetta, have built three separate versions of the EmDrive". This is wrong, at least according to Fetta. Fetta invented what he calls a "Cannae Drive" (http://en.wikipedia.org/wiki/EmDrive#Cannae_drive) which resembles an EmDrive but supposedly works on a different principle. In particular, Fetta believes that his drive requires radial slots in the chamber to operate. To test this, two versions of the Cannae Drive were (also, separately from the EmDrive test) tested by NASA: one with and one without the slots. Those tests both produced the same thrust (30-50 microN, about half what the EmDrive produced), which disproves Fetta's theory as to how the Cannae Drive is supposed to work.... and nothing else.
The null test device that everybody is so dismissedly claiming claiming disproves the EmDrive wasn't even supposed to be an EmDrive! Fetta, inventor of the Cannae Drive, was disproven. Shawyer, inventor of the EmDrive, was actually vindicated because according to his theory, the Cannae Drive (slots or no) is basically an inefficiently-shaped EmDrive.
I don't know why this is so hard for people to understand.
There's no place I could be, since I've found Serenity...