“Time is an illusion” (Albert Einstein)
Despite the fact that nothing could be more intuitive to people than dealing with the past, present and future of time, behavioral models can suffer from confusion due to an inattention to the matter of time. Analyzing how we human beings think about and relate to time in our everyday lives sheds new light on how the complex behavior of systems can be represented. We note that the past is easily represented on a timeline, because past events are seen, in hindsight, as occurring linearly. Processes represented as flow charts or activity diagrams usually appear to be happening in the present, as if all action were taking place in the infinitesimally short period of time we know as the present moment. The future, in contract, is seen as a landscape full of tasks to be done—each assigned a start time and an intended, at least, finishing time.
Time itself, however, knows nothing of our distinctions of past, present and future. Time, and our models of behavior in time can use these insights to capture more intuitive views of the processes and system usages we model as part of our system design process.
Most behavioral models in use today are either solely present-oriented, with no sense of past or future, or are only past or future oriented with no ability to show processes occurring in the present. In addition, current models impose a false precision on timed events in the future, forcing, for example, tasks on a Gantt chart to be specified to the day and hour, even years in advance, when no such precision actually exists.
This session will examine these dynamics and propose a new approach to modeling behavior in time based on the use of the Timebox. Timeboxes, together with process and usage modeling, can represent complex system and system-of-systems behavior to facilitate system design, verification and validation.