A General Temporal Theory
Jixin Ma, B. Knight · The Computer Journal · 1994
In this paper, a first-order theory of time is proposed as an underlying framework for most of the representative temporal models in artificial intelligence. The theory treats both points and intervals as primitive on an equal footing, and is shown to be powerful enough to subsume the interval based theories of Allen and Hayes, the point based theories of Bruce, of McDermott, and the interval and point based theories of Vilain and Knight and Ma. The approach is different from that of Ladkin, of Van Beek, of Dechter, Meiri and Pearl, and of Maiocchi, which is either to construct intervals out of points, or to treat points and intervals separately. Formal definitions are presented to characterize the open and closed nature of primitive intervals. The axiomatization allows non-linear time structures such as branching time and parallel time. Additional axioms specifying the linearity and density of time are separately presented.