For example, a second order system can be defined by two(minimal realization) or more state variables.

According to, "A minimal realization of such a relationally determined space-time structure can be found".

It has been shown that the class of 2-EPT densities is closed under many operations and using minimal realizations these calculations have been illustrated for the two-sided framework in Sexton and Hanzon.

In control theory, given any transfer function, any state-space model that is both controllable and observable and has the same input-output behaviour as the transfer function is said to be a minimal realization of the transfer function.