Why Physicists Accept Backradiation

                                                A reductionistic description of Reality.

Why do not physicists object to the notion of "backradiation" between two (black)bodies A and B in radiative contact? Because physicists are reductionists and argue like this:

• Both A and B emit radiation with emission spectra according to Planck's Law, and emission means sending out photons or light particles. There is thus a two-way flow of photons between A and B. Now if A is warmer than B, then A emits more energetic photons  and thus will win the battle and transfer some of its surplus heat energy to B. To understand this it is enough to understand how one photon is emitted and absorbed, and this is what a physicist is trained to do.

This is reductionism at its best. What is wrong with this? 

What is wrong is that both A and B consists of 10^23 atoms and interact by electromagnetic waves through a vacuum continuum, and this situation cannot be described by looking at a single photon. The radiative contact between A and B is an emergent phenomenon described  by Maxwell's equations in a vacuum continuum, as analyzed in model form in Computational Blackbody Radiation. As an emergent phenomenon the radiative transfer of heat energy is one-way from warmer to colder, and the two-way flow of light particles has here no role to play.

So how do we know that emergent continuum wave mechanics gives a better description than a reductionistic one photon? Because it is closer to reality. Reality is not a single photon. Reality is an emergent phenomenon of many interacting "particles", in resonance. Wave mechanics can describe reality, single-particle mechanics cannot.