# Modeling Time

## Abstract

In a simulation, the system being emulated is called the physical system. The behavior of the system is modeled in terms of state, objects and their attributes, events and time. In a simulation, state is defined by a collection of variables that describe the physical system at any point in time. Changes in the physical system are realized in the simulation by updating one or more of the variables. An object is any component in the physical system that requires explicit representation. The properties of a given object are called attributes. An event is an instantaneous occurrence that changes the state of the system. Each event has a time associated with it indicating when the event occurred. Time in the simulated system is represented as a totally ordered set of values, where each value represents an instant of time in the physical system being modeled. From this brief description of a simulation, it is clear that time is an integral part of how simulations represent the real world. This chapter will start by defining a temporal framework - how time is represented in simulations. The framework includes five dimensions: Time, Clocks, Time Flow, State Updates and Interactions. Each of these dimensions will then be described in greater detail.

## Keywords

Time Stamp State Update Synchronization Algorithm Causal Order Land Plane## References

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## Additional Reading

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