skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Probabilistic description of radioactivity based on the good-as-new postulate

Journal Article · · Am. J. Phys.; (United States)
DOI:https://doi.org/10.1119/1.11892· OSTI ID:5754135

The good-as-new postulate applied to radioactivity says: the conditional probability that a radioactive atom will live past time s + t, given that it has lived past time s, is equal to the unconditional probability that it would have lived past time t, starting from time zero. This postulate leads directly to the conclusion that the decay time of a radioactive atom is an exponentially distributed random variable. Add the postulate that the decay times of individual atoms in an aggregate of identical radioactive atoms are independent, and a complete description of the random behavior of an aggregate can be constructed. This approach stresses from the outset the randomness inherent in the radioactive decay process, and is offered as a complement to the deterministic approach that treats fluctuations about mean values. All results are exact within the context of the model and are applicable to aggregates of any size - no assumptions about large numbers are required. 1 figure, 1 table.

Research Organization:
Univ. of California, Livermore
OSTI ID:
5754135
Journal Information:
Am. J. Phys.; (United States), Vol. 47:2
Country of Publication:
United States
Language:
English