That's the OP's point. The EmDrive is utter quackery. It cannot exist because it necessarily violates the laws of thermodynamics. Anything that disproves those will literally undermine the entire foundation of what we understand about the universe. It would be directly comparable to discovering that the earth is flat.
We already know the laws of thermodynamics has exceptions. In very small systems, the entropy of a system fluctuates randomly - up and down. A light ray traveling over extremely long distances will have its energy reduced through red shifting, and that energy doesn't "go" anywhere, it is destroyed. In both of these regimes, over extremely small scales and extremely large scales, there are exceptions carved out of the laws of thermodynamics.
We know for certain that our understanding of physics is incomplete. General relativity (as formulated) is certainly wrong, because it precludes the possibility of small things existing; and yet they do. Quantum mechanics (as formulated) is certainly wrong, because it precludes the possibility of curved spacetime, and yet we know spacetime is curved.
There is, of course, a minuscule possibility that the emdrive actually works. It almost certainly doesn't. Ballpark one in a thousand. But we can't exclude the possibility that it works, based on the principle that the the laws of thermodynamics, which already has two exceptions, cannot have a third exception.
There's big talk about humanity traveling to other stars, colonizing other star systems, colonizing the galaxy and so forth. For this to happen, we would have to be wrong about physics. There's simply not any way to do it by building on the foundation of what we understand about the universe. So investing in low probability speculative ideas like emdrive is still necessary, even though for any given idea, there are lots of nines that say it won't work.
No, they don't. The "laws" you learn in high school are large scale approximations to the actual rules, which is codified in stat mech.
It's like claiming solids are not solid because atoms... Of course physicists know all this.
>General relativity (as formulated) is certainly wrong, because it precludes the possibility of small things existing
Having worked on GR stuff for a long time, this is news. GR most certainly allows any size thing to exist - it's a continuous theory.
>Quantum mechanics (as formulated) is certainly wrong, because it precludes the possibility of curved spacetime
No, it does not. QM in curved spacetime is so old and well understood it has a Wikipedia page [1] - from which you can start digging back into the literature.
You should really google such claims when making them to be sure you understand what you're claiming.
What an exciting time we live in, where links between quantum mechanics, thermodynamics, and GR May finally be emerging in physics! What will the final ramifications be? Hopefully something new comes of it.
If there are cases where conservation laws break down, or physical principles constrain one another in unforeseen ways, and they can be accessed at human scale, what an exciting thing! I’d guess you mostly feel this way too if I have not yet imposed any quackery on you, and suppose where we diverge is I do not see the harm in exploration as far out as the experimenter can dream to go. —Even if there is no theory for it. I know, the horror!
Do I think it will work? Well heck no. But that does not mean I wish the attempt to be quashed like I’m the inquisition. On the contrary, I bid them good luck. And if they do have good luck, they better have some results that are easily duplicated. I hope they do overthrow the foundations of physics. Why not? The earth will still possess curvature, and all the extant physics will still be as approximately right, and beautiful, as it was yesterday.
The guy had an experiment, his explanation for the results were utter quackery. I don't think the people at NASA expected his explanation was the right one, but they didn't have one so they replicated. MIT had an explanation of the results that was not due to thermal effects, and wasn't the originator's explanation. It didn't upend thermodynamics. The problem wasn't people exploring a tricky experiment, it was people buying in to a specific explanation of the experiment prematurely.
That's the OP's point. The EmDrive is utter quackery. It cannot exist because it necessarily violates the laws of thermodynamics. Anything that disproves those will literally undermine the entire foundation of what we understand about the universe. It would be directly comparable to discovering that the earth is flat.