Ethan Siegel is a name familiar to people following the LENR story, as he has been quite a strong critic of the E-Cat and other LENR devices since he doesn’t think they can work, based on his understanding of physics.
Now he has turned his attention to another controversial technology that has been making news: the EmDrive. Recently a paper published by a team from NASA has concluded that the EmDrive does produce thrust, without the use of propellant. Siegel has written an article for Forbes, titled “How Physics Falls Apart If The EMdrive Works” (http://www.forbes.com/sites/startswithabang/2016/11/23/how-physics-falls-apart-if-the-emdrive-works/#68e8665a4b0c), in which he examines the implications for physics, if the EmDrive does actually work as the NASA paper reports.
He states that if the EmDrive really does produce thrust without any kind of propellant, then we must throw away Newton, Einstein and any other physics built on the principle of conservation of momentum. He says this would be a very radical thing to do, since so many experiments over the centuries have verified Newton’s laws. He thinks the most likely thing is that there really is some kind of thrust being produced by the EmDrive, probably electromagnetic in nature; or, that the NASA researchers were simply mistaken in what they reported.
Roger Shawyer, the inventor of the EmDrive, also doesn’t think that Newton’s laws are violated by his machine. He has stated:
“What I would say is that the idea that EmDrive violates the laws of conservation of momentum is itself nonsense. Of course it doesn’t. It wouldn’t work if it did. All that EmDrive is a device for exchanging the momentum of the electromagnetic waves going up and down inside it, with the momentum of the thruster as it accelerates. It’s all actually elementary physics.”
Regardless of whether physics is broken or intact, there’s a lot of new interest in the EmDrive, and it does seem that the race is on to see if practical technology can be derived from it. There’s quite a lot of coverage about it in the news these days; see the current spate of articles that is gathered by Google News here+.