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/sci/ - Science & Math

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7479249 No.7479249 [Reply] [Original]

At what point does practical application override scientific understanding? Or does it ever?

If the EM Drive works, it could revolutionize space travel. Why not bugger all the understanding and testing here on earth and just drag one into space to see if it works? Skip all the bull on Earth, screw the testing in manufactured conditions, screw the understanding of the numbers and principles, and just put it in space. If it works, great, NOW we'll get to understanding it. If not, fine, we can finally put it to rest.

>> No.7479331

Moving things into space is expensive and there is a lock of good reasoning to believe the thing actually works. So far, it looks like every other instance in physics of people getting to hyped up to notice their shit is all retarded (see n-rays).

>> No.7479332

>>7479331
If i were to strap an EM drive to each shoe, how large would they need to be for me to fly?

>> No.7479333

Theory helps us understand experimental results. Theory dies not let you reject experimental results.

The experiment will measure what it measured. Only application of their which guide refined following experiments can make sense of experimental results.

You faggots know the theory that someone else proposed and forget that science is rigorous experiments.

>> No.7479335

>>7479249
Do you have $100,000 to design, build, paperwork and launch the test vehicle?

It takes time, effort, money and expertise. Do you have those resources?

>> No.7479349

>>7479249
okay, you pay for it.

>> No.7479410

>>7479332
Realistically? A bit bigger than your mother. Then their tips would be close enough to the sun for it to draw you off the surface of the earth.

>> No.7479421

>>7479249
practical application overrides scientific understanding immediately. If something works, you don't need to understand how it works to use it. Understanding would be great, but its not necessary.

Consider bicycles, there's no good explanation for why a moving bicycle is so much easier to stay on than a stationary one.
>inb4 gyroscopic effects
They've built bikes that would minimize them specifically to test that, and they were still easy to balance when moving.

>> No.7481198

>>7479333
>Theory dies not let you reject experimental results.

No, but it gives us extraordinarily good reasons to doubt them.

>> No.7481206

it already is known to work tard. its confirmed. conservation of motion doesnt apply to light. just because you have been in the remedial classes all your life doesnt mean every one else has

>> No.7481210

>>7479332
>If i were to strap an EM drive to each shoe, how large would they need to be for me to fly?
What makes you think it could lift itself in 1G, let alone the nuclear reactor you'd need to power it?

Even if it works, it's competing with ion drives and such, and NO they can't lift themselves in 1 g.

>> No.7481212

>>7479421
>there's no good explanation for why a moving bicycle is so much easier to stay on than a stationary one
It's because you can constantly correct your balance by steering with the handlebars.
Do you even Google?

>> No.7481233

>>7479335
>$100,000
you are off by two orders of magnitude.

Takes at least $10M just to book the orbital flight.

>> No.7481252

>>7481212

do you even bike with no hands?

>> No.7481256

>>7481198
Very true...
Here is a reasonable video demonstrating thrust according to an experiment done for the Boeing aircraft company-

http://m.youtube.com/watch?v=5P3pzbEnwuA

>> No.7481265

What ever happened to the E-cat?

Didnt people independently verify that as well?

We should strap an E-cat onto the meme drive, bet it will go FTL then.

>> No.7481276

>>7481212
Is that not because the movement changes the location of the center of gravitational pull allowing for the object to remain upright so long as it has the speed?

>> No.7481287

>>7481256
>Not conducted in vacuum
The potential for erroneous thrust due to heating and air currents is just too large. I'm not convinced.

To be convinced the EmDrive actually worked as claimed, I'd need a test which occurred:

>1. In a high vacuum
>2. Capable of showing it had carefully accounted for other potential sources of noise, such as electromagnetic interference or electromagnetic interactions with the test stand and powerlines
>3. With a (reversible) thrust signal of 1 mN or greater on a testing stand capable of uN accuracy

If such a test came up positive, and ideally was replicated by another group, I would believe without significant doubt that the EmDrive was really producing thrust of some kind. I probably still wouldn't believe it was producing reactionless thrust by Shawyer's hypotheses, but I would absolutely believe that it was generating real thrust.

>> No.7481292

>>7481212
Even if there's no rider, a moving bike will stay upright. You can even kick them, and they'll self-right.

>> No.7481372

>>7481287
Eagleworks got thrust in high vacuum months ago. It the thrust didn't meet your arbitrary Newton milestone.

I hate /sci/ because you fuckers are so goddamn ignorant.

>> No.7481378

>>7481265
that's how you construct a nyan cat

>> No.7481384

>>7481372
I know they did! I was paying attention. More to the point (because I don't quite trust Eagleworks), another independent lab got a replication in vacuum recently as well.

The reason I picked that "arbitrary" thrust milestone isn't arbitrary at all. Right now the thrust signals have all been near the limits of the detector's sensitivity, making error a real possibility. A larger thrust would allow a thrust signal to be completely unambiguous, especially because a magnitude that high would eliminate most sources of error that could produce signals of uN magnitude.

Bringing it into the mN range would bring it into the measurement range inhabited by ion drives, which I know we can accurately measure and separate real thrust signals from noise.

>> No.7481425

>>7481384
Also, scaling up to mN would vastly assuage my confidences that this was a real, scalable engine and not some other effect. If the thrust could actually be increased through increasing power or a different cavity design, I would be far more convinced that the microwaves bouncing around inside the cavity are actually the force-producing element here.

The other reason I am not currently convinced by the vacuum tests is that I'm not convinced all sources of noise are accounted for. The EagleWorks vacuum data still hasn't made it into an actual published source yet (last I checked, the source was a forum post on NasaSpaceFlight.com) and the vacuum replication I saw that *was* published (which was really very solid and substantially decreased my doubt that the EmDrive was actually producing thrust) did still have a potential major source of error which had not been accounted for (magnetic interactions with the powerlines) which did appear to be large enough that it could introduce serious error into the thrust signals. That's why I specified also showing that potential error from the powerlines would need to be characterized and accounted for to fully convince me.

I have studied the existing tests and evidence and find them interesting but unconvincing. The conditions I've described would eliminate pretty much all of my current objections and move me from "OK, the EmDrive can't possibly work as claimed, so these signals are probably error" to "OK, the EmDrive probably can't work as claimed, but there sure is thrust coming from somewhere - why does it work and will whatever-it-is actually scale to a useful thruster?"

>> No.7481434

>>7481252
>do you even bike with no hands?
>Implying that's much easier than balancing while standing still

>>7481292
>Even if there's no rider, a moving bike will stay upright.
...until it falls over.
>You can even kick them, and they'll self-right.
No, they don't.

>> No.7481440

>>7481434
http://ezramagazine.cornell.edu/SUMMER11/ResearchSpotlight.html

Yes, it will fall over eventually as it slows down, but while it's at speed it's quite stable.

>> No.7481463

>>7479249
Because at current thrust levels, that would actually be a *worse* way to find out. Things in orbit aren't in perfect free fall - there's atmospheric drag, perturbing forces from tides and the Earth's imperfect sphericality, the Earth's magnetic field, solar wind ...

For an effect as tiny as the handful of microNewtons the current EmDrive tests are run at, we actually wouldn't be able to tell if it was working at all because the environmental disturbances would overwhelm its minuscule acceleration.

On Earth, in a controlled environment, it's much easier to get precise measurements - and at these thrust levels, they must be precise, to tell if they even exist at all.

>> No.7481504

>>7481440
Color me skeptical, but it doesn't matter, since your point ultimately refutes >>7479421
>there's no good explanation for why a moving bicycle is so much easier to stay on than a stationary one.

>> No.7481526

>>7481504
Consider this. We didn't know this until the experiment was performed. We didn't really grasp how bikes were so stable until 2011. And there's a chance that even this doesn't fully explain it. Yet we've still been using bicycles for over a hundred years. We didn't need to fully understand them to use them.