I vaguely remember the inventor's theory on how it worked. It's an artifact of the speed of light being constant in all reference frames. If there is a pressu

I vaguely remember the inventor's theory on how it worked. It's an artifact of the speed of light being constant in all reference frames. If there is a pressure inside the chamber, intuitively the outside net force would be zero. But with light it's different due to the constant velocity. If the pressure was caused by little particle bouncing against the chamber walls, their velocities would counter each other as they bounced the chamber around. Velocities with light don't add that way. I may have gotten some of it wrong, but that's how I recall it.