Everytime a photon leaves an atom, the energy of that photon is matched by the increase in binding energy of that atom - right? If so would the change of energy in the form of radiation be equivalent to the change of binding energy? Is the aggregate binding energy of particles in the universe increasing with time? It is possible in an eternal cyclic universe for radiation to come back and decrease the binding energy particles, replenshing light elements such as hydrogen? Is it possible in the Big Bang theory?