Violation of Conservation of Energy?? Most of us know that for an observer inside a train travelling at a constant speed, with a light source in the middle of the train travelling towards two detectors fixed at the two ends would observe the order of events quite differently to a stationary observer. This demonstrates the break down of simultaneity. But nevertheless, the "the physical laws still remain the same in all inertial frame of reference". But it doesn't seems to be the case for virtual particles. Virtual particles are created due to the uncertainty in energy. From my limited knowledge quantum physics, the instance when a virtual particle has appeared, an antiparticle of the virtual particle must also appear to "cancel out" the effect to save the law of conservation of energy. But as we know, from the above, simultaneity does not exist for observers in different frame of reference. So, is the law of conservation of energy violated, or is this a flaw of the law of equivalence, or both altogether?