  To formulate a universal framework of information theory is beneficial. This
study proves that the sextuple model of the objective information theory (OIT)
is a sufficient and necessary condition for discussing information with four
basic postulations. It is demonstrated for each metric defined in the OIT,
there is a corresponding example in classical information theories or commonly
used principles. Furthermore, atomic information is defined as the indivisible
elementary information and the volume additivity is proven for combinations of
atomic information. Consequently, the information volume that a single quantum
carrier can carry is derived and a theorem relating information volume to mass,
energy, and time is proved. All these efforts illustrate that the OIT is a
novel information theory that can unify a variety of classical information
principles and even accurately reveal the quantitative relationship between
information, matter and energy.
