It works in practice, but does it work in theory?
New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
21–30 of 38 posts
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#22Earlier quoted context omitted.
What tablet did god write this law on?
Well, you're right that it's not a mathematical certainty that momentum is always conserved. But there's such a mountain of evidence for it that we should have a very high bar for claims that it's violated. Thermal effects and measurement error are both likely sources of the discrepancy. But another reason to be skeptical is that Noether's Theorem tells us that a violation of conservation of momentum is only possible…
... or the law was bypassed, somehow. Also huge news if confirmed
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#23Earlier quoted context omitted.
How many times do these results need to be replicated before you'll believe them? So far the thrust results have been replicated more than the majority of economics and social science research (i.e. more than zero times).
It violates the conservation of momentum; so it needs to replicated many many times.
[deleted]
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#24Ah, not this again. Just because they are NASA doesn't mean they are immune from pseudoscience.[1][2] [1] http://www.preposterousuniverse.com/blog/2015/05/26/warp-dri... [2] http://blogs.discovermagazine.com/outthere/2014/08/06/nasa-v...
Firstly, warpdrives aren't pseudoscience. The author is not claiming that they presently have a warp-drive. They are merely claiming they have some evidence that one might be theoretically possible. This isn't that inconceivable, sure it might take a thousand years before we could actually implement it.
Finally about the "EMDrive" there's no reason to believe that energy isn't escaping it, but that it's doing so in a way that something might be learned outside of imprecise measurements.
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#25Earlier quoted context omitted.
How many times do these results need to be replicated before you'll believe them? So far the thrust results have been replicated more than the majority of economics and social science research (i.e. more than zero times).
It violates the conservation of momentum; so it needs to replicated many many times.
How do you know that?
Consider a pretty simple and obviously correct device: an electric engine with an internal rotating shaft + a solar panel to power it, floating in space. The faster it rotates, the higher its acceleration in the gravitational field.
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#26Earlier quoted context omitted.
It violates the conservation of momentum; so it needs to replicated many many times.
How do you know that? Consider a pretty simple and obviously correct device: an electric engine with an internal rotating shaft + a solar panel to power it, floating in space. The faster it rotates, the higher its acceleration in the gravitational field.
The engine would spin, but it would have 0 velocity unless it sent out something as exhaust.
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#27Earlier quoted context omitted.
Yeah, we're going to learn that some experimenters are sloppy.
Its amazing to me how many people who purportedly believe in science act more like priests than scientists. Science is about drawing conclusions from empirical data, not ignoring empirical data that doesn't jive with your predetermined conclusions.
Yes, you must draw conclusions from empirical data. However, there is a likelihood, and there is a prior. The emdrive has no theoretical basis, so the prior is very low. The likelihood is small but not very small, because the results are just about at the detection limit. They claim that thrust is linear in the 40-80 watt range at 1.2mN/kW. Rather than go to the press, why don't they just turn up the power until the effect can't be denied? The fact that they did not publish that is also information.
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#28Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#29Earlier quoted context omitted.
Yeah, we're going to learn that some experimenters are sloppy.
How many times do these results need to be replicated before you'll believe them? So far the thrust results have been replicated more than the majority of economics and social science research (i.e. more than zero times).
> So far the thrust results have been replicated more than the majority of economics and social science research (i.e. more than zero times).
No, they haven't
Re: New NASA Emdrive paper shows force of 1.2 millinewtons per kilowatt in a Vacuum
#30Earlier quoted context omitted.
The science is pretty settled here. No such thing can exist by laws of physics. You might as well try making a perpetual motion machine or homeopathic medicine.
>The science is pretty settled here. No such thing can exist... Thanks, this more neatly sums up the attitude I was attempting to describe then anything I could come up with. The hubris that is endemic in much of the "scientific" community is simply amazing. Another glaring example of the gap between education and intelligence.
Extraordinary claims need extraordinary proof and until now there is no single proof or theory.
so yes, it is not hubris, it is science.
> Another glaring example of the gap between education and intelligence.
Pot kettle?