# Is there any chance that the EM drive thrust could be caused by quantum tunnelling? [duplicate]

So, I know you guys probably hate this topic, but I don't think stop looking into it is the solution. Figuring out what's wrong with the experiments would also bring new knowledge to the table, and make future experiments even more careful (The Opera neutrinos are an example of that).

What I'm asking is: is there a possibility of a quantum phenomenon, like quantum tunneling, being able to produce the amount of thrust observed in the experiments (which is tiny, but seems to me way higher than it would be expected by particle quantum tunneling, that is, if quantum tunneling can even transfer momentum. I'd argue it can, since its nothing more than a particle going from a higher "energy state" to a lower one, but the fact that it does this in a non-classical way, collapsing its wave function in a "region" where the classical possibility for the partical to be should be zero makes me wonder).

Quantum tunneling may play a whole, but if it does, is it so huge to the point of explaining the thrust? And is there any fringe reason why would quantum tunnelling would transfer so much momentum, given that it would happen so rarely in the EM drive device, if it would account for all the reported thrust, there would be some serious imbalance in the equations, as if tunneling borrowed energy from somewhere else, energy it shouldn't have if the particle would remain classically contained.

As I said, maybe not exactly quantum tunneling, but something else. We learned about hawking radiation somehow recently, Can you, quantum physicists, envision an effect that would account for that thrust being measured? I know the standard explanations, like "pushing into the vacuum", and other things.

I doubt any of you guys haven't spent at least some time entertaining the notion of the EM drive not being a fantastic beast, but simply something that needs an explanation as to how it works. I really doubt that, if it works, it would violate conservation of momentum. We just don't see how it would be possible without that violation, so we push it aside. That's, in my opinion, not a thing scientists should do. They should instead be trying to disprove the EM Drive beyond a shadow of a doubt, and if they can't they should start focusing on how it fits the standard model, and if it doesn't...! Well! How great would that be? How much new reasearch could be derived from it? who would be the first to win the Nobel prize on this matter? Isn't new physics all you guys have been looking for? what if you don't need LHC to get it, but simply a bizarre thrust obtained from turning on a round-frustrum shaped microwave oven?

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• Have a look at quantum tunneling hyperphysics.phy-astr.gsu.edu/hbase/quantum/barr.html . The energy is the same. For photons also the momentum. – anna v Jan 18 '17 at 17:39
• Downvoting not because EMDrive questions are deeply uninteresting and unproductive (which is certainly the case), but because of the quasi-mysticism over (and deep misunderstanding of) quantum mechanics and quantum tunnelling. Tunnelling is known physics and it obviously obeys the momentum conservation theorems that come with all of known physics; if it wasn't then this would have come up in the thirties. – Emilio Pisanty Jan 18 '17 at 20:04
• I know 2 things: My guess was a wild one, trying to make sense of something that apparently doesn't. I know Quantum Tunnelling doesn't normally break any physics. All I was saying was: "what if in this special case, somehow quantum tunnelling plays a role?" The other thing I know is: the thrust is there. People make this experiment at their homes and the thrust is there. Labs make the experiment under controlled conditions and the thrust is still there, so if nobody can explain it, I suppose my guess is just as good as anyone else's. Something we can't see must be happening. – FinnTheHuman Jan 19 '17 at 1:14