Minimal history, a theory of plausible explanation

In computational theory, time is defined in terms of steps, and steps are defined by the computational process. Because steps can be described, a computation can be recorded as a binary string. This allows time to be measured in bits, which in turn, allows the definition of various computable complexity measures that account for the minimal amount of computation required to create an object from primitive beginnings. Three such measures are introduced in this article. They are “transcript depth,” which is closely relate to logical and computational depth, and “Kd complexity,” which is similar to Levin's Kt complexity, and “minimal history.” The later two measures are comprehensive in the sense that they characterize all information required for the creation of an object and also all computable internal relationships and redundancies that are present in the object. © 2007 Wiley Periodicals, Inc. Complexity 12:48–53, 2007