**2. Nature of temporal (t > O) universe**

As we accepted subspace and time are coexisted within our temporal (t > 0) universe [4, 5], time has to be real, and it cannot be virtual since we are physically real. And every physical existence within our universe is real. The reason some scientists believed time is virtual or illusion is that; it has no mass, no weight, no coordinate, no origin, and it cannot be detected or even be seen. Yet time is an everlasting existed real variable within our known universe. Without time there would be no physical matter, no physical space, and no life. The fact is that every physical matter is coexisted with time which including our universe. Therefore, when one is dealing with science, time is one of the most enigmatic variables that ever presence and cannot be simply ignored. Strictly speaking, all the laws of science as well every physical substance cannot be existed without the existence with time. For which we see that; time cannot be an independent dimension or an illusion. In other words, if time is an illusion, then time will be independently existed from physical reality or from our universe. And this is precisely that many scientists have treated time as an independent variable such as Minkowski's space [2], for which we see that Einstein 's space–time can curve time. However if matter can curve time–space, then we can change the speed of time. But as I see that it is our universe exists with time, it is "not" our universe changes time.

Since time is a constantly moving dependent variable at a constant pace, for scientific presentation we usually use numeric symbols to represent time otherwise it would be very difficult to facilitate and to understand the nature of time. For convenience we had divided time into past (i.e., t < 0), present (i.e., t = 0), and future (i.e., t > 0) domains to represent time, as exemplified in **Figure 1**.

From which we see that our universe changes with time; for example present moment at t = 0 moves immediately forward to become the next present moment (t + Δt). In other words the present moment t = 0 becomes the moment of past. Once the present moment (t = 0) moves forward a section of Δt ! 0, no matter how small it is, it is impossible to return back, since our universe changes with time. From which we also see that it is impossible to move the current moment (t = 0), no matter how small Δt is, ahead or behind the pace of time. Nevertheless this diagram exemplifies our temporal (t > 0) universe changes with time, since our universe is a stochastic dynamic temporal (t > 0) space [4, 5]. Of which we see that it is impossible to travel backward or ahead the pace of time.

Since past time domain (i.e., t < 0) represents the moment of certainty events (e.g., past universes), they were the past memories (i.e., information) but without physical substance in it and no time. Which is similar as viewing a backward video clip, if we move time backwardly (t < 0), we see that past consequences (i.e., past universes) changes with time (e.g., t = � tn) as a backward movie clip. In view of Einstein's general theory of relativity as I quote; matter (i.e., time–space) curves (or changes) time–space. And this is precisely the section of past time (i.e., t < 0)

*Temporal (t > 0) Space and Gravitational Waves DOI: http://dx.doi.org/10.5772/intechopen.99474*

### **Figure 1.**

*Shows that our temporal (t > 0) universe changes naturally with time, in which it shows the age of our universe is about 14 billion light years old. The past time domain (t < 0) represents a set of certainty virtual events (i.e., past universes), the future time domain (t > 0) represents a physically realizable domain of uncertainty. And the instantaneous present moment (t = 0) is the only moment of absolute physical certainty. Yet we see that present moment is instantaneously moved forwardly to become the next new present moment [(i.e., t = 0 + Δt) where Δt* ! *0], to next absolute certainty moment.*

domain that Einstein used to derive his general theory, by which his theory had have treated time as an independent variable. This is precisely why general theory is a deterministic theory instead indeterministic. Which is similar to most of the classical sciences are deterministic, yet science is supposed to be non-deterministic or approximated.

Nevertheless within our temporal (t > 0) universe, time is a dependent or interdependent variable with respect to the subspace since space and time are coexisted. In which we see that future events (i.e., t > 0 domain) are nondeterministic consequences with degree of uncertainties. And this is the positive time [or temporal (t > 0)] domain that Einstein general theory may not apply within t > 0 domain, since subspaces are not deterministic (i.e., our universe changes with time). Nevertheless the implication of temporal (t > 0) is that physical realizable events exist if and only if within positive time domain, by which the instantaneous t = 0 can only be approach but never be able to attain (i.e., t⟶0), even assumed we have all the energy (i.e., ΔE) to spend.

To further epitomize the nature of our temporal (t > 0) universe, I have come up with a composite diagram as depicted in **Figure 2**, which shows that our universe started from a big bang creation, although time has been existed well before the creation. Since the past certainty consequences (i.e., memory spaces) were happened at specific time within the negative time domain (i.e., t < 0), we see that every specific past time event had have been determined with respect to a specific past certainty subspace. From which we see that time can be treated as an independent variable with respect to the past certainty consequences in the pass-time domain (t < 0) as from mathematical standpoint. But from physical reality standpoint, time is no longer existed within the past time (t < 0) domain. And this is precisely why time can be treated as an independent variable from mathematical analysis to predict what would happen at a distant future, but with some degrees of uncertainty since physical substance or subspace changes naturally with time.

This is precisely what classical laws and principles had done to science, using past deterministic certainties to predict the future. Since prediction is supposed to be non-deterministic (i.e., uncertainty), yet all the predicted solutions were

**Figure 2.**

*Shows a composited temporal (t > 0) time–space diagram to epitomize the nature of our temporal universe. BLY is billion of light years. In which instant-present moment t = 0 is the only moment of absolute physically certainty of our universe. Past time domain (t < 0) shows past certainty universes but without time and no physical substance. And future time domain (t > 0) represents a physically realizable domain that changes with time.*

maintained deterministic. it is because deterministic analysis produces deterministic solution. In other words all physically realizable solutions strictly speaking should be temporal (t > 0) solution. From which we see that all the laws, principles, theories as well paradoxes were developed from the deterministic past certainties to predict the future uncertainty consequences, but in reality, those laws and principles should not deterministic instead of deterministic. From which we see that Einstein's general theory of relativity cannot be the exception [2]. But using past deterministic to predict the future consequence is likely be deterministic, that contradicts with our temporal (t > 0) universe, which is a non-deterministic universe (or subspace) constantly changes with time.

Although using past certainties to predict future outcome is a reasonable method that had have been using for centuries, but it is physically wrong if we treated time as an independent variable within our temporal (t > 0) universe. From which we see that irrational, weird, and fictitious solutions emerged, which had had already been dominating the world-wide scientific conspiracy. This includes Schrödinger 's fundamental principle of superposition [6], Einstein's special and general relativity theories [2], Hawking's space–time [7] and others. Since they were all developed from the past certainties to predict the deterministic future, but future prediction physically cannot be deterministic or certainty.

Nevertheless the section of time Δt shown in **Figure 2** represents an incremental moment after the instant t = 0 moves to a new t = 0 + Δt, where Δt can be as small as we wish (i.e., Δt⟶0). Yet we will never be able to squeeze it to zero (i.e., Δt = 0) and this is the section of time that cannot be delay or moved ahead the pace of time (i.e., t < 0 + Δt or t > 0 + Δt) or even stop. From which we see the aspect for time traveling either ahead or behind the pace of time is inconceivable, since we are coexisted with time.
