6 ms·

> If this works by impelling against the Earth's magnetic field That's a completely different premise than the em-drive has, though. It's supposed to not depen

by dom0 10y ago

> If this works by impelling against the Earth's magnetic field That's a completely different premise than the em-drive has, though. It's supposed to not depend on an external field; developing a force between two magnets wouldn't exactly qualify as (non-)rocket science today.

matheweis 10y ago
But it would represent an improvement on what we have today, which is a finite amount of fuel use to keep the satellite in orbit that eventually runs out.
stale2002 10y ago
The way science works is by doing experiments. The people have been doing experiments on the EM drive and have been getting unexpected results. Nobody really knows why yet, but that's kinda the point. Is thermodynamics flawed? Is it pushing off of "dark matter"? Is it a completely new and novel scientific effect? Any of these circumstances would be interesting.
- DanielBMarkham 10y ago
  Yes. Even if it's the most likely thing, experimenter error, for a half-dozen teams to all have errors and not spot them? That's quite interesting! It's the same situation we had with the FTL neutrinos a while back.
  - euyyn 10y ago
    Except the neutrino paper then was a big lot of physicists asking colleagues to help them review, so as to find where the problem was. What I see here is just hype. The former, as opposed to the latter, is what gives confidence that the people involved are doing their darnest not to fool themselves. That what they're doing is actually science.
    - DanielBMarkham 10y ago
      I don't know. I see a few universities looking into building their own setup. I see the Chinese filing patents, testing them in orbit. I see a 2017 microsat launch. I see a healthy debate continuing over on the reddit Emdrive board. That doesn't look like people trying to sell things to me. That looks like a lot of different people from different backgrounds playing around with an experimental setup that does something unexpected. The only difference I see is that with the FTL neutrinos, folks were saying this breaks a mathematical model that we've proven over and over again. With the emdrive, folks are saying If this works, it's by some model we do not yet understand. It doesn't attempt to disqualify an existing model; it suggests there's some other model applicable that we don't quite understand yet. For most folks, this is quite more upsetting than the FTL guys. I get that. Still, observe first, theorize second. I'm sure the theory folks will catch up, and it'll probably be some sort of EM leakage we're talking about. But maybe not. Maybe we've accidentally come up with a new kind of photon rocket. That's what makes the story fun.
      - euyyn 10y ago
        > It doesn't attempt to disqualify an existing model It would very much disqualify conservation of momentum, which is another way of saying that the laws of motion are the same here and one meter down the road. Conservation of momentum has been observed in countless experiments for centuries, in a broad range of conditions. It was indeed observed first; there's no catching up needed for the theory. It's always valuable, and in a sense exciting too, to test it again beyond the range where it's already been tested, even if you expect a negative result (the null hypothesis holding). But that's not what's happening: If your goal is to learn, and you see momentum not being conserved in your prototype space engine, you start dismantling it, simplifying it, until you stop seeing it. And then go back one step to see it again. Your device might not be a space engine anymore! But now it's simplified; easier to reproduce, and easier to model and analyze. The laws of nature don't care about the purpose and coolness of your device, they apply the same. You also take your measurement apparatus and calibrate it against something unrelated, in many conditions, to make sure it's not lying. You might have a different goal than learning: to achieve cheap space travel, which is a great thing. If then you build a prototype space engine with the hope that it won't conserve momentum, and you see a positive result, there's already the first red flag. If when you see that, what you do is trying to explain it with new (or with wrong) theory instead of questioning it, there's the second red flag. Healthy debates, and playing with technology in a lab, are good things. But not all good things are science. Our minds are too easy to fool, and people are doing this without condoms.
cjensen 10y ago
The "premise" for the em-drive has been determined to be a thorough misunderstanding of the physics involved, so you cannot rule out any potentially contributing force in the experiment. Yes you heard that right: guys who misunderstand physics go and design a reactionless thruster which, when measured in their shoddy experimental setup, produces a measurable thrust. If there really is a measurable thrust, then the Laws of Motion are wrong and General Relativity is wrong. I'm disinclined to believe that long-held principles of physics will be upended by some guys who designed something based on a misunderstanding.
- freehunter 10y ago
  You sound very negative towards conducting more experiments on this, when the results have been unexpected every time it's been tested. You're displaying the kind of dogma that science has been fighting against since the dawn of time. Either it's true or it's not, but we can't tell until we test it. And so far, it's only been disproven in theory, not in practice. That's worth more experiments.
  - cjensen 10y ago
    Occam's Razor says it is not true. If you read the linked article, it is saying, in the most polite and disinterested way possible, that it is not true although they allow, in the driest of terms, that it could be true. I expect if the same authors analyzed the Loch Ness monster or Big Foot, they would also disinterestedly point out the unlikelihood of either and point out the how awful the proofs put forth are while admitting there is no categoric proof that the monsters don't exist. Pons and Fleischmann were straightforward in their error. This is bozo territory.
    - bicubic 10y ago
      I don't expect the em-drive to work, but the parent post has a point. We've had repeated experiments yielding unexpected results. It's worth an inquiry; if nothing else, to thoroughly explain what went wrong so the same mistake is avoided in future experiments. Outright dismissing new ideas, no matter how far-fetched, is very much the antithesis of the scientific principle. You mustn't forget that everything we take as indisputable fact today, was an outrageous far-fetched theory at some stage. It was barely yesterday that Barry Marshall was ridiculed for proposing that stomach ulcers are bacterial, because everyone 'knew' that bacteria can't survive in such an environment.

by dom0 10y ago

matheweis 10y ago

But it would represent an improvement on what we have today, which is a finite amount of fuel use to keep the satellite in orbit that eventually runs out.

stale2002 10y ago

The way science works is by doing experiments. The people have been doing experiments on the EM drive and have been getting unexpected results. Nobody really knows why yet, but that's kinda the point. Is thermodynamics flawed? Is it pushing off of "dark matter"? Is it a completely new and novel scientific effect? Any of these circumstances would be interesting.

DanielBMarkham 10y ago
Yes. Even if it's the most likely thing, experimenter error, for a half-dozen teams to all have errors and not spot them? That's quite interesting! It's the same situation we had with the FTL neutrinos a while back.
- euyyn 10y ago
  Except the neutrino paper then was a big lot of physicists asking colleagues to help them review, so as to find where the problem was. What I see here is just hype. The former, as opposed to the latter, is what gives confidence that the people involved are doing their darnest not to fool themselves. That what they're doing is actually science.
  - DanielBMarkham 10y ago
    I don't know. I see a few universities looking into building their own setup. I see the Chinese filing patents, testing them in orbit. I see a 2017 microsat launch. I see a healthy debate continuing over on the reddit Emdrive board. That doesn't look like people trying to sell things to me. That looks like a lot of different people from different backgrounds playing around with an experimental setup that does something unexpected. The only difference I see is that with the FTL neutrinos, folks were saying this breaks a mathematical model that we've proven over and over again. With the emdrive, folks are saying If this works, it's by some model we do not yet understand. It doesn't attempt to disqualify an existing model; it suggests there's some other model applicable that we don't quite understand yet. For most folks, this is quite more upsetting than the FTL guys. I get that. Still, observe first, theorize second. I'm sure the theory folks will catch up, and it'll probably be some sort of EM leakage we're talking about. But maybe not. Maybe we've accidentally come up with a new kind of photon rocket. That's what makes the story fun.
    - euyyn 10y ago
      > It doesn't attempt to disqualify an existing model It would very much disqualify conservation of momentum, which is another way of saying that the laws of motion are the same here and one meter down the road. Conservation of momentum has been observed in countless experiments for centuries, in a broad range of conditions. It was indeed observed first; there's no catching up needed for the theory. It's always valuable, and in a sense exciting too, to test it again beyond the range where it's already been tested, even if you expect a negative result (the null hypothesis holding). But that's not what's happening: If your goal is to learn, and you see momentum not being conserved in your prototype space engine, you start dismantling it, simplifying it, until you stop seeing it. And then go back one step to see it again. Your device might not be a space engine anymore! But now it's simplified; easier to reproduce, and easier to model and analyze. The laws of nature don't care about the purpose and coolness of your device, they apply the same. You also take your measurement apparatus and calibrate it against something unrelated, in many conditions, to make sure it's not lying. You might have a different goal than learning: to achieve cheap space travel, which is a great thing. If then you build a prototype space engine with the hope that it won't conserve momentum, and you see a positive result, there's already the first red flag. If when you see that, what you do is trying to explain it with new (or with wrong) theory instead of questioning it, there's the second red flag. Healthy debates, and playing with technology in a lab, are good things. But not all good things are science. Our minds are too easy to fool, and people are doing this without condoms.

cjensen 10y ago

The "premise" for the em-drive has been determined to be a thorough misunderstanding of the physics involved, so you cannot rule out any potentially contributing force in the experiment. Yes you heard that right: guys who misunderstand physics go and design a reactionless thruster which, when measured in their shoddy experimental setup, produces a measurable thrust. If there really is a measurable thrust, then the Laws of Motion are wrong and General Relativity is wrong. I'm disinclined to believe that long-held principles of physics will be upended by some guys who designed something based on a misunderstanding.

freehunter 10y ago
You sound very negative towards conducting more experiments on this, when the results have been unexpected every time it's been tested. You're displaying the kind of dogma that science has been fighting against since the dawn of time. Either it's true or it's not, but we can't tell until we test it. And so far, it's only been disproven in theory, not in practice. That's worth more experiments.
- cjensen 10y ago
  Occam's Razor says it is not true. If you read the linked article, it is saying, in the most polite and disinterested way possible, that it is not true although they allow, in the driest of terms, that it could be true. I expect if the same authors analyzed the Loch Ness monster or Big Foot, they would also disinterestedly point out the unlikelihood of either and point out the how awful the proofs put forth are while admitting there is no categoric proof that the monsters don't exist. Pons and Fleischmann were straightforward in their error. This is bozo territory.
  - bicubic 10y ago
    I don't expect the em-drive to work, but the parent post has a point. We've had repeated experiments yielding unexpected results. It's worth an inquiry; if nothing else, to thoroughly explain what went wrong so the same mistake is avoided in future experiments. Outright dismissing new ideas, no matter how far-fetched, is very much the antithesis of the scientific principle. You mustn't forget that everything we take as indisputable fact today, was an outrageous far-fetched theory at some stage. It was barely yesterday that Barry Marshall was ridiculed for proposing that stomach ulcers are bacterial, because everyone 'knew' that bacteria can't survive in such an environment.