  The operator of time formalism is applied to radioactive decay. It appears
that the proposed approach offers better insight and understanding of the
phenomena in a way that the decay exponential-law becomes the Boltzmann
distribution in Gibbs treatment of canonical ensemble. The radioactive decay is
seen as temporal canonical ensemble where the radioactive constant appears as
the analog of the absolute temperature multiplied by Boltzmann constant. The
stochastic character of decay process becomes plausible in the proposed
approach and the explanation why decay is characterized by constant, and not by
some parameter, is offered.
