Constitutive functions must be introduced into the mesoscopic balances, like in the macroscopic theory
. Here the choice is only indirectly restricted by the Second Law of thermodynamics, which is not directly applicable to the mesoscopic description, but of course is valid for the averaged macroscopic quantities, because the macroscopic quantities are constructed from the mesoscopic ones by averaging [4,5]:
Further, it might be noted that, while a large number of Santilli's applications refer to what are essentially small systems and thermodynamics is a macroscopic theory
, exactly how thermodynamics will apply in these cases is not yet completely clear.
But there is a far greater irreversibility present here: the theory indicates we can devise no thermal system at all that will ever evolve by conduction alone into a pair of cubes in contact, one of uniform high temperature, the other of uniform low temperature.(7) So there are temperature distributions which (so far as the standard macroscopic theory
are concerned) can never be the end product of any process of conduction.