Or, it's a scientific breakthrough. That won't happen often, but it also can't be ruled out completely.
The likelihood that free momentum and free energy are possible is indistinguishable from 0. They are empirically impossible in the strongest reasonable sense the word can have.
And the experiments didn't make it obvious that the setup didn't work. I mean, I don't think anyone took the inventor's theoretical claims seriously, but the device did generate some small thrust in a difficult to explain way.
Besides, we know that space isn't nothing, so being able to tractor against whatever is there would be a rather intersting engineering find; physicists would then likely take the experiment and go "oh, there's a neat edge case in this system of equations that explains it". There are a lot of interesting edge cases left to find and engineer.
Momentum is conserved independently, it can not be created from energy without spilling some the other way (into whatever you're pushing against).
The vacuum is a translation invariant state so you can't push against it to get momentum either, but you can create particles out of it and then push against those. That's what electro magnetic thrusters do. They generate photons. The effect is just super tiny.
Well, if one know how to create such an effect...
We have a model of our perception of the universe
On the other hand, the universe is nothing more than the set of constraints that we call "science". The universe is the model, and science is an effort to duplicate that model.
If it was to me, I don't agree. Science is a collection of human ideas that exist in the minds of humans. As another commenter said, it's our model of the universe. There is no difference between science and our understanding of science unless you're talking about differences in understanding between individual people.
> On the other hand, the universe is nothing more than the set of constraints that we call "science". The universe is the model, and science is an effort to duplicate that model.
The reason that we know this is far stronger than simply: "It hasn't been observed yet". That would allow that any new thing could end up violating the established rules.
It could be that if you write the one hundred millionth Mersenne prime on a cookie, and the one two hundred millionth on a banana they start circling each other and create free energy. This claim has not been falsified. So on what grounds do we rule it out? Because it is incompatible at an incredibly deep level with everything we know about cookies, bananas, and how their physical properties depend on what's written on them.
Every aspect of each of these objects that has ever been observed has been found to be describable in terms of some unbelievably simple mathematical structures. For these unbelievably simple mathematical structures we have prove that anything that can be described by them does not allow free energy.
An observation like the Mersenne, cookie, banana interaction can not violate the mathematical derivation, therefore it implies that out of all the infinitude of observations that have been made of bananas and cookies, that all were describable by energy and momentum conserving physical theories, somehow this one arbitrary one is special. It can not be described by even the type of mathematics we have hitherto used and yet was completely invisible.
How could that be? Flying Spaghetti Monster of course. Just as the FSM hid the true age of the earth from us by interfering with science, so it also conspired to hide the free energy Mersenne Banana Cookie interaction from us.
In other words: If you know that the FSM did not create the earth 4000 years ago, then you even more definitely know that there is no free momentum/energy. If you think that we can't know either of these things, then your concept of knowledge sucks.
It's improbable to flip a coin 10 times and get head ten times. It's for all practical purposes impossible to do so 10^10 times. This level of mathematical probability is functionally indistinguishable from 0 thus it is entirely accurate to call it impossible.
It's not logically impossible of course, it just happens not to be possible in our universe. It's physically impossible. Like the prime cookie. The appropriate amount of time spent on investigating prime cookies is not "very small", it's 0.
Now there is of course reason to investigate the EM Drive to some degree: To figure out where the bug was. To learn about potential experimental errors. As a puzzle, to solve the apparent paradox. But any other framing of the issue is dishonest.