NASA has published their findings that microwave thrusters, generally believed to be impossible, actually work in spite of the fact that they violate the law of conservation of momentum. British scientist Roger Shawyer invented the EmDrive several years ago, and Chinese scientists confirmed its functionality last year in a test that produced 720mN of thrust, which is enough to power a satellite, but the West didn’t pay much attention. The NASA team tested a slightly different model built by US scientist Guido Fetta, and were able to produce 30-50 mN, significantly less than the Chinese team, but enough to prove the theory. So how does it work? NASA isn’t claiming to know.
"Test results indicate that the RF resonant cavity thruster design, which is unique as an electric propulsion device, is producing a force that is not attributable to any classical electromagnetic phenomenon and therefore is potentially demonstrating an interaction with the quantum vacuum virtual plasma."
“Interaction with the quantum vacuum virtual plasma” means that the thruster may work by pushing against the electromagnetism and particles that pop in and out of existence in empty space. So it makes total sense that no one understands why this engine works. No one understands why quantum particles do anything. Mostly. Or maybe The End of Mr. Y’s hypothesis is correct, and Shawyer has a mind powerful enough to think universal law into existence. Who knows.
But for now, why it works is less important than that it works. The implications of these findings are huge, because microwave thrusters don’t require any propellent and can be powered by solar energy, so they can operate in perpetuity unless the hardware malfunctions. This could change space travel forever. Propellent (like rocket fuel) is expensive and makes up the majority of the weight of any launch, and when it runs out, the engines stop. With a microwave thruster, the trip to Mars would take weeks rather than months. Deep space exploration would be possible. Basically, start filling out your Starfleet application.
Obviously, the experiment will be scrutinized and replicated before the results are totally accepted. But this is exciting. Something new is happening in physics, and it has cracked the ceiling wide open. Our science fiction future awaits.