5 ms·

I've been following this story pretty closing for several months now. So here's the opinion of an actual research scientist. Q. Does the Em drive produce thrus

by searine 11y ago

I've been following this story pretty closing for several months now. So here's the opinion of an actual research scientist. Q. Does the Em drive produce thrust? A. Undetermined. Several tests from multiple independent labs have reported thrust, including in a vacuum. However several of the labs that reported positive thrust come from a sketchy background. Q. Does it violate conservation of momentum? A. Undetermined. There are several competing theories trying to explain the phenomenon, but we lack raw data. I think the last thing anyone wants to see here is "new physics". Q. Roger Shawyer seems like a scummy kook? A. Yes. This is why more testing is really important. Q. What about more tests? A. A few dozen people have taken it upon themselves to hack together emDrives and test them. The first couple so far were plagued by poor construction, RF interference, and poor experimental design. However, the hacking community is slowly getting its shit together. Q. Pluto in 18 months? A. If it works. My intuition screams "its cold fusion all over again", but there is still a chance.

p1mrx 11y ago
EmDrive and Cold Fusion are the perfect complementary technologies. Next someone should claim to invent a cooling system that doesn't reject heat, and we can start building Stargate Puddle Jumpers.
javert 11y ago
Thanks, nice summary. > I think the last thing anyone wants to see here is "new physics". I really want to see new physics, because I want to see us get off this rock and far away. I think most people want to see new physics. I think that's why this topic is so popular. That said, I can understand physicists not wanting to see new physics. Wait. In a way, that sentence is crazy. In a way, physicists should want to see new physics more than anybody. Where does the "not wanting to see new physics" sentiment come from? Just not wanting to be wrong?
- homborg 11y ago
  I read it as: we want a better explanation, than just: "new physics!"
- davesque 11y ago
  Maybe not wanting to see new physics before seeing rigorous, reproducible experimental results? Kind of a cart before the horse thing? Just guessing.
- thaumaturgy 11y ago
  Laymen tend to underestimate the very vast body of research which supports current physical models. "New physics" would imply that something has been fundamentally wrong with physics for a long time, and that is unlikely.
  - javert 11y ago
    I get that.
- cabinpark 11y ago
  I'd love to see new physics! Every physicist I know loves new physics. But if you claim to violate the conversation of momentum, everyone is going to be skeptical and not believe it. We have hundreds of years of experiments and observations that support the law and have looked in many places from small to large and not seen violations. This is what makes people not believe it and thus physicists are going to assume you are wrong and not physics. It's not so much a negative concern, but more of a practical one. But should it be tested in a rigorous manner and reproduced, then physicists will believe it. It's just it hasn't and thus we are going to stick with the established very well understood and tested theory. Like are you sure you have properly counted all the initial momentum? Are you 100% you are not introducing energy to the system? The possible explanations is long and a good experiment will eliminate as many of these as possible. As an example, look at the OPERA experiment which found to have superluminal signals. New physics? Nope, just a faulty piece of equipment. BICEP showing gravitational waves? Nope, just poor data interpretation and neglecting interstellar dust. So if you want to claim new physics, be damned sure you have ironclad proof.
  - ttctciyf 11y ago
    > Every physicist I know loves new physics. If physicists don't want new physics, they should stop doing research!
    - javert 11y ago
      Only as long as the new physics is in your little sphere of influence so you can keep the grant money gravy train flowing. Presumably.
  - javert 11y ago
    That makes sense, but that's not how I interpret "nobody wants to see new physics" in the ancestor comment. (But who knows.) I mean, wouldn't it be really frustrating to find out the law of conservation of momentum is not universal? Exciting, but also frustrating? Maybe even embarassing for physics? It would be like someone proving P=NP.
- DenisM 11y ago
  99.99% of the time when "new physics" is invoked, it amounts to crookery or kookery. Nobody wants to see that, because it takes energy to disprove even the obviously flawed claims, and the energy is taken away from more promising endeavors, that are usually less appealing to the public. "Free Energy" is very appealing, so is "10x better batteries", "10x more flash storage", "momentum-defying space thruster", and so on. These modern-day fairy tales are gaining press simply because people want them to be true, not because they actually show a path for progress. Similarly, a promise of a "miracle cure" is very appealing to the public, and so it may seem cynical to downplay any such claim right away, but it has absolutely nothing to do with actual advances in medicine.
eevilspock 11y ago
> I think the last thing anyone wants to see here is "new physics". The article's responds with the nonsensical "Some damage to our theories of physics is an acceptable payoff if we get a working space drive." EDIT: Let me clarify why it's a nonsensical statement: First, I think it meant to say "cost", not "payoff". Second, there would be no cost. None of the things we were able to do with our existing theories would be lost. We'd only be pushed to refine the theories (or in rare cases come up with an entirely new theories) that would be at least as accurate as the prior theories and cover phenomenon the old didn't. If anything, we'd be able to go back and do better at all the things to which we'd applied the old theories. It's like saying "Some damage to Newtonian physics is an acceptable cost if we get a working understanding of relativity and gravity." Einstein did no "damage" to Newtonian physics. He made it better.
- evincarofautumn 11y ago
  Well, it’s improbable, not nonsensical. If someone goes and implements a technology that trounces our working theories, we certainly need to update those theories. It’s just that that’s exceedingly unlikely to happen.
  - nickff 11y ago
    Photoelectric cells were invented before we understood the photoelectric effect, alcohol and preserves were used to store drinks and foodstuffs before we understood microbes, forging and annealing used before anyone had a theory on metallic crystal formation, and incandescence was used before anyone understood electromagnetic radiation; to name but a few examples. Why would it be surprising that someone invented a device which functions in a manner which is not understood?
    - thaumaturgy 11y ago
      Oh! This is one of my favorite questions about scientific progress. People seem to regard scientific progress as this kind of wave function, where some theory comes along and then some other theory or discovery disproves the previous one and so on and so forth. But if you want to think of scientific progress that way, then you have to think of it as a dampened sine wave (https://en.wikipedia.org/wiki/Damped_sine_wave https://en.wikipedia.org/wiki/Damped_sine_wave) -- that is, discoveries and theories tend to refine previous discoveries and theories, and scientific progress over the millenia has been rapidly zeroing in on the truths of our reality. What is left at this point is mostly things at very large scales -- cosmological stuff like dark matter, dark energy -- and very small scales -- stuff like sub-subatomic particles and the Higgs boson and the nature of mass and so on -- and very complex things like biology and climate science. What isn't left at this point is a revision of the laws of conservation. It is exceedingly unlikely that anything will be discovered at any point in the future which will do anything other than add perhaps the very smallest of exceptions to those laws, and even then, I doubt very much that will happen. So, essentially, the age of physics discoveries in garages is mostly over. There will be many more discoveries in physics, but they now require the collective efforts of entire nations.

by searine 11y ago

p1mrx 11y ago

EmDrive and Cold Fusion are the perfect complementary technologies. Next someone should claim to invent a cooling system that doesn't reject heat, and we can start building Stargate Puddle Jumpers.

javert 11y ago

Thanks, nice summary. > I think the last thing anyone wants to see here is "new physics". I really want to see new physics, because I want to see us get off this rock and far away. I think most people want to see new physics. I think that's why this topic is so popular. That said, I can understand physicists not wanting to see new physics. Wait. In a way, that sentence is crazy. In a way, physicists should want to see new physics more than anybody. Where does the "not wanting to see new physics" sentiment come from? Just not wanting to be wrong?

homborg 11y ago
I read it as: we want a better explanation, than just: "new physics!"
davesque 11y ago
Maybe not wanting to see new physics before seeing rigorous, reproducible experimental results? Kind of a cart before the horse thing? Just guessing.
thaumaturgy 11y ago
Laymen tend to underestimate the very vast body of research which supports current physical models. "New physics" would imply that something has been fundamentally wrong with physics for a long time, and that is unlikely.
- javert 11y ago
  I get that.
cabinpark 11y ago
I'd love to see new physics! Every physicist I know loves new physics. But if you claim to violate the conversation of momentum, everyone is going to be skeptical and not believe it. We have hundreds of years of experiments and observations that support the law and have looked in many places from small to large and not seen violations. This is what makes people not believe it and thus physicists are going to assume you are wrong and not physics. It's not so much a negative concern, but more of a practical one. But should it be tested in a rigorous manner and reproduced, then physicists will believe it. It's just it hasn't and thus we are going to stick with the established very well understood and tested theory. Like are you sure you have properly counted all the initial momentum? Are you 100% you are not introducing energy to the system? The possible explanations is long and a good experiment will eliminate as many of these as possible. As an example, look at the OPERA experiment which found to have superluminal signals. New physics? Nope, just a faulty piece of equipment. BICEP showing gravitational waves? Nope, just poor data interpretation and neglecting interstellar dust. So if you want to claim new physics, be damned sure you have ironclad proof.
- ttctciyf 11y ago
  > Every physicist I know loves new physics. If physicists don't want new physics, they should stop doing research!
  - javert 11y ago
    Only as long as the new physics is in your little sphere of influence so you can keep the grant money gravy train flowing. Presumably.
- javert 11y ago
  That makes sense, but that's not how I interpret "nobody wants to see new physics" in the ancestor comment. (But who knows.) I mean, wouldn't it be really frustrating to find out the law of conservation of momentum is not universal? Exciting, but also frustrating? Maybe even embarassing for physics? It would be like someone proving P=NP.
DenisM 11y ago
99.99% of the time when "new physics" is invoked, it amounts to crookery or kookery. Nobody wants to see that, because it takes energy to disprove even the obviously flawed claims, and the energy is taken away from more promising endeavors, that are usually less appealing to the public. "Free Energy" is very appealing, so is "10x better batteries", "10x more flash storage", "momentum-defying space thruster", and so on. These modern-day fairy tales are gaining press simply because people want them to be true, not because they actually show a path for progress. Similarly, a promise of a "miracle cure" is very appealing to the public, and so it may seem cynical to downplay any such claim right away, but it has absolutely nothing to do with actual advances in medicine.

eevilspock 11y ago

> I think the last thing anyone wants to see here is "new physics". The article's responds with the nonsensical "Some damage to our theories of physics is an acceptable payoff if we get a working space drive." EDIT: Let me clarify why it's a nonsensical statement: First, I think it meant to say "cost", not "payoff". Second, there would be no cost. None of the things we were able to do with our existing theories would be lost. We'd only be pushed to refine the theories (or in rare cases come up with an entirely new theories) that would be at least as accurate as the prior theories and cover phenomenon the old didn't. If anything, we'd be able to go back and do better at all the things to which we'd applied the old theories. It's like saying "Some damage to Newtonian physics is an acceptable cost if we get a working understanding of relativity and gravity." Einstein did no "damage" to Newtonian physics. He made it better.

evincarofautumn 11y ago
Well, it’s improbable, not nonsensical. If someone goes and implements a technology that trounces our working theories, we certainly need to update those theories. It’s just that that’s exceedingly unlikely to happen.
- nickff 11y ago
  Photoelectric cells were invented before we understood the photoelectric effect, alcohol and preserves were used to store drinks and foodstuffs before we understood microbes, forging and annealing used before anyone had a theory on metallic crystal formation, and incandescence was used before anyone understood electromagnetic radiation; to name but a few examples. Why would it be surprising that someone invented a device which functions in a manner which is not understood?
  - thaumaturgy 11y ago
    Oh! This is one of my favorite questions about scientific progress. People seem to regard scientific progress as this kind of wave function, where some theory comes along and then some other theory or discovery disproves the previous one and so on and so forth. But if you want to think of scientific progress that way, then you have to think of it as a dampened sine wave (https://en.wikipedia.org/wiki/Damped_sine_wave https://en.wikipedia.org/wiki/Damped_sine_wave) -- that is, discoveries and theories tend to refine previous discoveries and theories, and scientific progress over the millenia has been rapidly zeroing in on the truths of our reality. What is left at this point is mostly things at very large scales -- cosmological stuff like dark matter, dark energy -- and very small scales -- stuff like sub-subatomic particles and the Higgs boson and the nature of mass and so on -- and very complex things like biology and climate science. What isn't left at this point is a revision of the laws of conservation. It is exceedingly unlikely that anything will be discovered at any point in the future which will do anything other than add perhaps the very smallest of exceptions to those laws, and even then, I doubt very much that will happen. So, essentially, the age of physics discoveries in garages is mostly over. There will be many more discoveries in physics, but they now require the collective efforts of entire nations.