Earlier quoted context omitted.
The supposed thrust of the EmDrive is very small. But the device has a lot of wires with current that can be equivalent to an electromagnet, and very hot parts that can create air currents, and ... If you have not done few physics labs, it's easy to underestimate the measurement problems and the level of noise in experiments. Most of the Physics community thinks that this is an experimental error. One symptom is that…
I don't think the scientists at NASA are bogus. They managed to calculate when a probe would reach pluto that was only off by a few seconds. There is still a lot of research that needs to be done on that, but there are those that say it isn't breaking the laws of physics. We shall see I guess, but it has been replicated in 3 places now taht I'm aware of, two of which are serious science outfits.
In a "massless" thruster, the theoretical maximum Thrust/Power ratio is 1/c = 0.0033 mN/KW if you don't want to break the conservation of momentum, special relativity or quantum mechanics. You could get this value with an ideal perfectly efficient laser beam. The latest NASA version proclaims (50 uN / 50 W) = 1 mN/KW that is 300x the theoretical maximum, so if it's not an experimental error, it must be breaking some of the currently supposed physic laws.