On Tue, Mar 15, 2016 at 10:24 AM, David Roberson <dlrober...@aol.com> wrote:
I would assume that the guys working on these devices have the expertise to > ensure that a very minimum amount of RF is escaping from their shielded > cavity. This is not too difficult to achieve in real life with highly > conductive cavities. > What if ensuring that a minimum of RF escaped made the thrust go away, and it was found that RF in the radio and infrared was benign and correlated with the thrust? > Also, the actual thrust due to photons being emitted is extremely tiny due > to their low mass when compared to the overall device. > The common understanding is that photons have no mass at all. But it is easy to see how they can carry significant momentum in the case of the recoil of an atom when a gamma photon is emitted during a transition from an excited state. Radio and infrared photons do not have this kind of momentum. But perhaps if you have a high intensity, and the beam is focused, there will be some thrust. Has anyone attempted to measure the thrust from a powerful flashlight, one wonders. Eric