To be fair - Eagleworks' statement on this wasn't presented as an academic paper claiming to be scientific research. The current interest is being generated by what is basically a progress report they gave to NASA.
Eagleworks presented their results at a conference (no idea if there's any refereeing process at that conference) with the proceedings published
here (full paper behind paywall). That's a claim that they did serious scientific research.
Unless, of course, it operation was based on something we don't yet understand - interacting with a virtual plasma, for example, that hauls away the momentum in a way we don't quite grok yet.
While possible, this is all ridiculously unlikely. First of all, Lorentz invariance --- special relativity --- have been tested extremely well here at earth. That means the vacuum respects relativity and doesn't carry momentum. Furthermore, unless you want to say that one part of the lab is somehow fundamentally different than another part of the lab, it's a
mathematical theorem that momentum is conserved. So, to get thrust, that engine would have to be exhausting something, even if we don't know what it is. So, we have three options: (1) The entire framework in which physics has been done for centuries has to be thrown out, and we understand nothing about how the world works, and all of our inventions are just lucky guesses,
or (2) The engine is somehow generating a new type of fundamental particle, which carries off non-zero momentum, providing thrust (there are lots of reasons this is hard),
or (3) The work that the original inventor and subsequent researchers have done is as poor as it looks on inspection and doesn't actually show anything besides systematic errors. Given that I just read enough of the inventor's "theory paper" to see an exhibition of complete misunderstanding of basic equations of electrodynamics, I know how I weigh the odds.
As we noted - Tesla did his work without believing in or understanding electrons - you don't need full understanding to make something that functions.
I want to make a clarification about Tesla, since he's come up a lot in this thread. His professional life was well after the basic principles of electrodynamics were worked out by physicists including Ampere, Faraday, and especially Maxwell (among many others of course). They didn't know about electrons, either, since they died before the discovery that matter is made of particles. But that doesn't matter. The classical theory of electrodynamics only needs the concept of charge to work perfectly well; Tesla knew this physics and had no problem believing in the concept of charge and current. So, despite his eccentricities and conflicts with the scientific knowledge of his day (basically refusing to accept experimental data because he didn't like it), he did understand extremely well the parts of physics relevant to electrical engineering. He wasn't just guessing and getting lucky.
Similarly, Brahmins in India immunized people from smallpox by applying scabs from the surviving afflicted to minor scratches on the as-yet uninflected, many hundreds of years before anyone understood or Eden suspected the existence of viruses.
Causation and effectiveness can often be figured out long before true understanding is reached.
Absolutely true, and there are different levels of true understanding. But it is a very different case. No one in India had centuries of evidence suggesting that it's impossible to immunize oneself from smallpox in that manner.
I feel like I've been saying the same thing a lot, so I'm now going to refer you to someone else who puts it pretty nicely. I urge you all to read the article that Dannyalcatraz posted near the top of the thread
from the Discover magazine blog, especially the last section. It's not about the money or the effort. That's such a small cost that it's fine to chase off-the-wall ideas. But there are other costs. Here's the best quote: "I am personally a huge space enthusiast; I would love to see a new type of propulsion that would make it easier to explore the universe. But having your heart in the right place is no excuse to walk away from normal critical thinking. It is not materially different than the approach of people who reject science when they don’t like what it says about climate change, vaccines, or genetically modified organisms."
Now the exhaustless engine has exhausted me!
