If you could travel back in time would you screw up the space time continuum? I mean could you just be an?

observer or would you get yourself involved and screw it all up for me and the rest of us ?
Aries your making me dizzy !

The Billiard Ball theory suggests that anything we do in the past will act to send us back in time again.

Also, anything that we do in the past, will already have happened to make today as it is. Fortunately this means we can't go back to screw it up anymore than it already is

No. Since you were not a time traveller in history, you would find yourself in an alternate timeline where you could do what you like without affecting your home timeline. But you would never be able to return to the original. You would return to that alternate's future.

You probably would if you think about it if you were to do something to mess up what is going to happen thing could turn totally around. Who knows if you do one little thing different than you did the first time then things could get a little crazy in the future. Wars could happen just from that one little thing, people would change. I know it sounds drastic, but here is a question some people ask if you had a gun with one bullet would you go back in time to when Hitler was a little boy and shoot him? If you said yes then think about what could, and probably would happen. People that met before might not meat some of your friends would not exist. Well i hope that helped you out.

If you see someone who looks exactly like you in a really old picture, then that means that at some point in time you went ,or will go, back in time.

But nothing you do in the past can affect the future because you would have already done it and nothing would have already happened, which is why you were able to go back in the first place.

But if you were to go back in time and do something silly like killing your father before he had a chance to concieve you, you would not exist from that point on and would be stuck, back in time, with no parental lineage.

As long as you stay "upstream" of the paradox while it occurs you will experience no adverse effect. However if you managed to get downstream into your original time, the entire timespace continuum would collapse up to conception point where time was so slow that it did not exist at all (existance=negligible). Pre big bang.

Luckily that is not possible in our Universe. In order to travel back in time, that would require a person to exceed the speed of light. We know that we cannot do that because it would take an infinite amount of energy to attain "c" and exceed it.

God knew we would meddle with things if we had that ability and that ability has not been given to us. It makes for nice Science Fiction, but that's about it.

I think that most people are so stupid that they'd go back in time to 'change things' and simply 'cause' the event they were trying to change or stop. That too, is a classic science fiction plot and it's been done to death.

Nobody realizes how the smallest actions at any one time could affect future events. For example, say that you were able to travel back in time and kill Adolf Hitler during WWI, or even kill his mother before he was born, who is to say that an even worse tyrant would evolve and destroy millions of lives? Remember, Josef Stalin was no nice guy and he KILLED millions of his own countrymen. Had he not been 'kept in check' by WWII and Hitler, maybe HE would have been worse than the two of them combined.

Had somebody nudged the gunman who killed Bhutto in Pakistan just a few inches, maybe his bullet would have missed and Pakistan would have a much different future now.

Had somebody warned JFK not to go to Dallas on November 22, 1963, he wouldn't have been killed there, and had he lived, we would NOT have gotten embroiled in Vietnam. Quite a different history, eh?

So nobody could be just an "observer". Their mere presence in the past could affect any number of outcomes of any number of situations. It's like ripples in a pond after you drop a pebble in the water. They spread out and eventually touch all parts of the pond shore.

If I could go back in time, there are a few things I'd change to try to avoid many of the screwups we have today. Why bother to go back as an observer? We have history books, movies, etc.
But we can't go back in time and never will be able to do so. We're stuck with what has already happened and have the luxury now of fixing things for future generations of daydreamers.