[Greysard]

A time cop from the future would actually not try to mess with the past, present or future, which, if he did, chances are that, even he would stop existing, and hence, no time cop.

Many a Sci-Fi story is written around the premise that the future is so bad that the time traveler goes back in time to change the history - at any cost, including his own existence. Terminator movies are just one example.

This, however, creates a paradox: if the time cop gets destroyed in the process of changing the past then who changed that past in the first place? One answer to that paradox is the concept of the fractal Multiverse where Universes copy themselves whenever a tiniest event takes place. One obvious question about that theory is that you can't copy a Universe without having an equivalent amount of energy or mass at hand.

[Lazamataz]

Many a Sci-Fi story is written around the premise that the future is so bad that the time traveler goes back in time to change the history - at any cost, including his own existence. Terminator movies are just one example. This, however, creates a paradox: if the time cop gets destroyed in the process of changing the past then who changed that past in the first place? One answer to that paradox is the concept of the fractal Multiverse where Universes copy themselves whenever a tiniest event takes place. One obvious question about that theory is that you can't copy a Universe without having an equivalent amount of energy or mass at hand.

There is a solution to this, but you have to be willing to think really hard when this video is playing.

[adorno]

This, however, creates a paradox: if the time cop gets destroyed in the process of changing the past then who changed that past in the first place?

That's what I had in mind when I said that the universe would be nothing but chaos. With chaos, nothing would ever get to fruition, because, it would have been undone by a time traveler, and then, even that undoing of events could get undone, and so on and so forth. Thus, chaos. But, perhaps there is a better plan, and time travel is "prohibited" by design, and thus, what we have is an ever-changing universe, headed in a single direction, and that's towards a future.