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Comment by Fjolsvith | Hacker News Reader

In case you missed it, the theory behind the EM Drive is also being used to explain galaxy rotation:

https://www.researchgate.net/publication/313580454_Low-accel...

I see no connection to the EM drive. The paper you mentioned suggests an alternative inertia formula, however it doesn't break conservation of inertia as far as I can see.

The "theory behind the EM drive" [1] is completely based on classical electrodynamics and therefore it's flawed. Classical electrodynamics conserves momentum and energy. It doesn't mean that the EM drive can't work though, it just means that this theory can't work.

[1] I only found this: http://www.emdrive.com/theorypaper9-4.pdf

Is this what you refer as the "theory behind the EM Drive"?

>Hubble-scale Casimir effect Isn't casimir effect very short range phenomenona? Seems like distances involved would reduce it to negligible levels compared with huge EM fields. Its like claiming weak nuclear force is relevant at galactic distances because "all the atoms add up". http://math.ucr.edu/home/baez/physics/Quantum/casimir.html

Why is it that EM advocates always seem to be dark matter-deniers? There's observational evidence for DM, a lot more than for the EM drive.

> There's observational evidence for DM

Um. Isn't that a contradiction in terms? By definition, DM is stuff whose existence is inferred by observations that contradict what we previously presumed to know. Hence postulate the existence of DM to close the gap between what we observe and what we "know".

There's observational evidence of something. Dark Matter is just the place holder for the something.

I don't know anything about this field but the language seems sound to me.

Is there a consensus on this interpretation v. "just adding more dark matter"?

> Is there a consensus on this interpretation v. "just adding more dark matter"?

This reminded me of https://xkcd.com/1758/

It is unfortunate that the theory of Dark Matter doesn't have a cute parlor trick like the EM Drive.

$200 bucks it doesn't pan out, what you say?

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