ABSTRACT
Time is not only the basic constituent of the existence, but it is also the crucial physical variable for every process, every motion, for the work of every dynamic system, hence for every control system. The behavior of every plant, of its controller and of its control system occurs in time. The physical reality, the human experience with it, the human understanding, the accumulated human knowledge lead to the following de…nition of time [170], [171]:
De…nition 2 [148] Time Time (i.e., the temporal variable) t (or ): - is an independent scalar physical variable, - its value called instant or moment determines uniquely when some-
body or something started/ceased to exist, - its values determine uniquely since when and until when somebody
or something existed/exists or will exist, - its values specify uniquely how long somebody or something existed,
exists or will exist, - its values re‡ect uniquely whether an event E1 occurs then when an-
other event E2 has not yet happened, or the event E1 took/takes/will take place just then when the event E2 was/is/will be happening, or the event E1 occurs then when the event E2 has already happened, - its value occupies (covers, encloses, is over and in) equally
everybody and everything everywhere and always, and - its value has been, is, and will be permanently changing smoothly,
strictly monotonously continuously, equally in all spatial directions and their senses, in and around everybody and everything, independently of everybody and everything.
