The EM drive has caused a lot of debate, in no small part due to the fact that it seems to violate the known laws of physics… and because other experimenters haven had difficulty replicating it. Well, it *seems* some experimenters have gotten it to work *and* have come up with an explanation for how it works… and how it works without busting Newtons laws.
In short: the “exhaust” spat out by the EM drive is just photons. It’s a photon rocket, something that has been understood for decades. But the EM drive has been confusing because it hasn’t been seen to emit photons. The theory here is that it *does,* though. But rather than just your standard flood of photons (such as you’d get from a flashlight, a laser, a microwave oven or a social justice warrior who has undergone spontaneous proton decay), in this case each photon is paired up with another. And the two are paired up in such a way that they cancel each other out… they are emitted, their momentum is transferred, but their not detectable because the crest of the wave of Photon A is matched with the trough of the wave of Photon B. Or so goes the theory, anyway.
Gotta admit this one is a bit of a headscratcher. On one level I get the idea of the waves cancelling each other out; junior high school double-slit experiment stuff. But imagine if the EM drive was *ridiculously* powerful. Say, it spat out a hundred megawatts of “invisible” energy. If you put something fragile and easily damaged behind it (like an industry standard Trigglypuff), you’d be dumping a whole lot of energy into it that’s undetectable. So does your Triggytarget burst into flames or not?
Buh.
