Random thoughts on "Time Traveling"

Okay, this is going to be one of the weirdest post that I have written yet!

It is a Saturday afternoon, feeling not very inspired; came across a documentary about Doctor Who, and some scientists discussing about time traveling... 

Not really paying attention to most of it, as I was also reading a mail...

someone commented: 

"we already know that it is possible to travel to the future, as your time slows down if you can travel very fast approaching the speed of light" (K's subconscious: I think I have heard Steven Hawking saying something similar).

someone else continued: 

"however, traveling back in time is really difficult, you can end up creating paradoxes by changing past event. For example, if you travel back in time and accidentally kills your grandfather (awful example!), then there wouldn't be you, which then means you wouldn't travel back in time, and your grandfather wouldn't be accidentally killed, and you would grow up, and invent the time machine one day, and travel back in time, and accidentally kills your grandfather"... you kind of end up in a loop?"

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I am sure many of you have seen lots of movies that portraits this "time travel paradox". By this time I was not reading my mails any more, it suddenly occurred to me why does all the films think there will be a paradox?

Imagine you are the clever chap (or girl) that will invent the time machine, and the first thing you would do is to travel back in time to inspire yourself. 

Wait a minute... have you ever met your future self all this time up to the point you invented the machine? You probably have not (or you would have done it a lot quicker), that just did not happen in your reality. So what happens when you travel back in time?

If you entertains the fact that time travel is possible, then you will probably accept the idea of parallel universes; different versions of reality if things were to happen differently, but as far as you (the observer) is concerned, your reality is the one that you live in now (the other possibilities didn't happen as far as you are concerned). 

What if by traveling forward in time you simply get to see the future in your version of the reality. But in order for you to travel back in time, you actually end up in a parallel universe, where traveling back in time (and all the consequences) is possible?

In which case there wouldn't be a paradox, because you went to meet your counterpart in another reality, this then triggers all other events that shapes that parallel universe (unlucky for you though, because I think you probably can't get back to your original reality anymore. Traveling to the future you will only see the future of that reality, rather than returning back to your original universe).

Time travel=Parallel universe travel

What if a machine that can travel back in time is necessarily a machine that can travel to parallel universes?, to other parallel realities similar but different to our own, where crazy scientists does travel back in time and accidentally killing their grandfathers and cause a mess. That could just happens to be the story of that reality (which we can see will ends somewhat differently to the one we live in now).

This also leads to other interesting thoughts. What if you travel back in time but really behave yourself and everything turns out to be the way they did in your own reality? Well, if all other observers (other people in that world) all end up where they ought to be, then there is no much difference between that world and your own world. You would still be stuck there (and nobody knows), which could be a possibility in your original world. So the two versions of reality can actually merges into a possibility at some point of time.

The observers (people), and to some lesser extents, things (objects, atoms, energy), actually seems to play very important roles here. if you travel to a inconsequential space-time points where there are no observers and don't touch anything or cause a explosion, then it is safe to assume that the world will probably turn out to be very similar up to the point you invent the time machine, if you travel forward.

On the other hand, there are fixed space-time points that can cause a lot of changes, where just by showing up you immediately create an alternative reality. Imagine interrupting a public speech or a TV show, there are too many observers, you change too many variables in a instant, the world/events therefore evolves differently from that point on and never develops in the same way as it did in your past.

    

I wonder if this actually make any sense to others.. but here you go.

Now can someone that is trained please write this up in Maths?