Posted on 11/11/2020 11:09:18 AM PST by BenLurkin
The "EmDrive" claims to make the impossible possible: a method of pushing spacecraft around without the need for — well, pushing. No propulsion. No exhaust.
But the EmDrive doesn't just violate our fundamental understanding of the universe; the experiments that claim to measure an effect haven't been replicated.
[A]ll forms of rocketry (and indeed, all forms of motion across the entire universe) require conservation of momentum. In order to set yourself in motion, you have to push off of something. Your feet push off of the ground, airplanes push themselves off of the air, and rockets push parts of themselves (e.g., an exhaust gas) out the back end to make them go forward.
But the EmDrive doesn't. It's just a box with microwaves inside it, bouncing around. And supposedly it is able to move itself.
Let's talk about the momentum part. Conservation of momentum is pretty straightforward: in a closed system, you can add up the momenta of all the objects in that system. Then they interact. Then you add up the momenta of all the objects again. The total momentum at the beginning must equal the total momentum at the end: momentum is conserved.
So, if the EmDrive demonstrates a violation of momentum conservation (which it claims to do), then this fundamental symmetry of nature must be broken.
But almost every single physical theory, from Newton's laws to quantum field theory, expresses space symmetry (and momentum conservation) in their base equations. Indeed, most modern theories of physics are simply complicated restatements of momentum conservation. To find a breaking in this symmetry wouldn't just be an extension of known physics — it would completely upend centuries of understanding of how the universe works.
(Excerpt) Read more at space.com ...
The theory behind the EM Drive treats it as a way to tweak the conservation of momentum, not to violate or repeal it.
Yeah but now they changed the name “phlogiston” to Dark Matter/ Energy
Yeah. Evil spirits changed the name...
Cold fusion deja vu all over again!
The rocket is pushing off of the exhaust gases.
It is a simple and imprecise but essentially accurate way to describe the law of conservation of linear momentum in third grade language used by most mass media.
Marooned off Vesta.
Throw mass in one direction, accelerate in the other.
If you have enough mass, water to burn so to speak, you can move without flame...
Newton’s Third Law of Motion.
I have been investigating ideas like this for a long time to the point where I realize chemical rockets aren’t the answer for most space travel.As far as chemical rockets go, Spacex is the real deal and have maximized value for this type by making them reusable and reasonably economical.The nuclear thermal rocket we designed in the 50’s is the best I’ve seen so far. As an EE and space enthusiast, I have also looked into my own non-chemical rocket designs as a ‘hobby’and I may have designed something better. It’s all on paper only, so I will build and test to see. This would be something the govt. should have, but there is no way in hell I’d give it to them if this election is stolen.
There not powering it properly. Power should be provided via an E-cat system.
ugh They’re
I’m impressed by the results of the DEm drive.
Creating marked paper out of nothing is an extraordinary accomplishment.
Em Drive is interesting, from what I hear everything is still inconclusive, with more evidence pointing to not.
Certainly once someone from earth has established a moonbase and maybe a mars outpost, then people will be in a better position to do experiments with all kinds of innovative drive ideas.
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