I have been intrigued by much of the research into laser weapons, photon weapons, and light in general. Perhaps the most intriguing question I have come across recently was the statement that photons have zero mass – which seems to invalidate the age old equation of F= MA because if M is zero than F is zero but more importantly Einstein’s equations were demonstrated when light was observed to bend in a strong gravitational field – thus photons have mass. But the response to this question was that photons have zero mass at rest but it has mass in motion. This of course means that the photon lies inert in some body but when that body has energy applied the photon escapes as light with mass. So now the question is how do you know that the source has inert photons? Just because they escape when energy is applied is not in and of itself evidence that the photon was in the source object but could just as easily have come from the energy source. But then this opens up another question and that is Newton’s law regarding the conservation of mass and energy. The photon must have existed somewhere prior to being observed but then if it has no mass but gains mass through motion then isn’t that a creation of mass or is it a conversion of energy to mass? If that is true then isn’t E=MC<2 either not true or is there a dimension to this as yet unobserved because that equation describes the force unleashed by this conversion which was the atomic bomb.
But the explanation of this also includes the statement that a photon gains mass through “momentum,” where the momentum is the product of the mass times the linear velocity (m=MV) but momentum has both magnitude and direction so it is a vector which complicates things somewhat but the essential question remains even when V approaches the speed of light although again this tends to complicate matters still further due to the law of conservation of momentum. However, Physicists have declared that while a photon at rest has zero mass it does have a non-zero momentum but this seems like a stretch given that momentum is based on velocity and a photon at rest cannot be in motion and if it is in motion then by definition it must have mass.
This leads me to some other questions for example we are told that when energy is applied to an atom the electrons surrounding become excited and jump to a higher ring but almost immediately they drop back losing energy as light. But if that lost energy shows as light (a photon) and that photon has mass where did that energy come from – the external source? Did the electron gain mass when it jumped from an inner ring to an outer one? If it didn’t and its mass did not change then did the energy absorbed by the electron convert to the photon mass? But how does that fit
with Einstein’s equation?
Although electrons are thought of as “particles” Quantum Theory increasingly leads to the conclusion that an electron is more like a force than a particle which leads to the conclusion that an electron’s mass is a product of its motion – in effect the momentum of the electron determines its mass and the momentum is determined by its velocity. But when you heat an object it may grow hot, distort, or suffer some change but the total mass doesn’t increase, but then mass is not truly weight but includes resistance to motion. Consequently a photon by definition is traveling at the speed of light and thus its mass must be infinite according to Einstein but doesn’t really just prove that a photon and thus our reality cannot go faster than a photon? On the other hand if you did exceed the speed of light doesn’t that just mean it would become invisible?
This brings us to the question of motion. Our entire universe is in motion from the galaxies to the atom. The atom is surrounded by electron rings which are in motion so it would be logical that if a photon resided within the atom it would have mass since it isn’t at rest because the atom and electrons are not at rest. Therefore, the logical conclusion is that the photon emitted by shift in electron energy is the result of the energy applied from some outside source exciting the electrons, but since that energy is converted to mass has the source of the energy been reduced in mass or energy?
If the excited electron never took on mass when moving to the higher state and never lost any mass when returning to its former energy level then where did the photon’s mass come from? It seems to me Physicists are trying to have it both ways. Light can be viewed as either a wave or a particle but if light is a wave it is in motion and thus must have mass. But if light is viewed as a particle it must have mass because it is in motion. In order for a photon to have a zero mass it must be at rest and in that case where does this at rest photon exist?