  A derivation of a theoretical, time average, cosmic microwave background
(CMB), Planckian temperature V of the universe remains a challenge. A scalar
potential model (SPM) that resulted from considerations of galaxy cells is
applied to deriving a value for V. The heat equation is solved for a cell with
the boundary conditions of SPM Source and Sink characteristics, with simplified
cell characteristics, and with zero initial temperature. The universe is a
collection of cells. The CMB radiation is black body radiation with the cells
acting as radiators and absorbers. Conventional thermodynamics is applied to
calculate V = 2.718 K. The temperature and matter content of cells are finely
controlled by a feedback mechanism. Because time is required for matter to flow
from Sources to Sinks, the radiation temperature of cells cycles about V after
an initial growth phase. If the universe is like an ideal gas in free expansion
and is not in thermal equilibrium, then the pressure and volume follow the
measured CMB temperature vm = 2.725 K. Therefore, increasing vm >V equates to
an expansion pressure on matter and expanding volume.
