Ah but I was arguing that the marble wouldn't loose mass because the energy it was loosing would be the energy of impetus applied by an external force for it to achieve escape velocity. The photons energy, speed and direction are an integral part of its generation. Nothing has been applied to it to get it moving on its way.
Another way of looking at it might be to consider the effect a black hole has on a photon of light. If from you arguement Phil we accept that light has mass then would it not also have dimensions of volume. If that's is the case then close to a black hole the photons of light would be physically stretched from the effects of different field strengths of gravity at one end of the photon compared to the other, stretching to infinity as one end of the light gets closer to the black hole and the other end reaches our recording equipment (at the other end of the universe). My thoughs are that if this were the case then wouldn't the photon light frequency remain the same but the intensity would diminish, whereas what we do see is a loss of energy through the increased red shift of the light.
Hyperthetically that is
