I am aware that the relativistic mass can be expressed in terms of rest mass and momentum, which seems to be the canonical explanation, but I am looking at an alternative way of visualising the increase in mass of a system with velocity.
My understanding is that the mass of a system (e.g., a particle) is accounted for by the energy of the force-carriers within it (plus the Higgs interaction, but ignoring that for now).
These being considered as waves, it seems that the frequency of these waves would be observer dependent and that a moving observer would measure (at least conceptually) the frequencies of the forces in the system differently than a stationary observer. I also note that the energy changes would be asymmetric depending on the relative direction of motion of the force-carrying particle being observed. So a particle moving directly towards the observer at 0.5C would have double the frequency and therefore twice the energy, whereas one moving directly away at 0.5C would have two-thirds the frequency and the energy, and so the net change would be an increase in energy. (These figures may be approximations).
My question is whether this simple re-accounting of the observed wave frequency and energy in the system in the new inertial frame would lead to a correct calculation of the energy of the moving system, or whether there is something else going on?
I realise that the question "is it a good model" is a matter of opinion, so that is not what I am asking. What I am wondering is whether it is fundamentally flawed, and if so, why?