I wasn't sure where to put this question, since it didn't seem to fit any category. However, because it brings up the topic of virtual particles, I'll ask here. From what I understand, virtual particles can travel faster than light, and it is virtual photons that are responsible for the attraction between two magnets. So my question is this: if there was a magnet that could supposedly be turned on and off, and there was a device that could detect the changes in that magnetic field from a distance away, would that device be able to pick up the changes as they happen (instantly)? Or would there still be some sort of delay?