  Considering our expanding universe as made up of gravitationally interacting
particles which describe particles of luminous matter and dark matter and dark
energy which is described by a repulsive harmonic potential among the points in
the flat 3-space, we derive a quantum mechanical relation connecting,
temperature of the cosmic microwave background radiation, age, and cosmological
constant of the universe. When the cosmological constant is zero, we get back
the Gamow's relation with a much better coefficient. Otherwise, our theory
predicts a value of the cosmological constant $2.0 10^{-56} {\rm {cm^{-2}}}$
when the present values of cosmic microwave background temperature of 2.728 K
and age of the universe 14 billion years are taken as input.
