This is not a 'Is time travel possible?' thread. With that said.

Imagine this scenario.
Its 2357, and you invent a time machine. You go back to the year 2003.

Now, the question is, could you really effect the future?
If you kill someone, were you meant to do it, as in they died in 2003, you just went back in time and you were the one who killed them. Or say you want to kill the president, so you try to kill him, say it was yesterday. But because he is living today, it was impossible to kill him.
Basically.
If you went back in time, do you really think you could affect the future? Why or why not?

I'm of the belief that time is "set in stone".
e.g. Everything is as it is because things happened in the past. Whether or not that was the work of a time traveller does not matter. Like if we found out that the wheel was invented by a time traveller who had the idea to go back and teach cave men how to make one, it still remains a fact that cave men made wheels.

I have a weird belief. Every possible action is a possible and existent future, and that if I were to go back in time and change something, the future I was in would still be the same but the future I go back to would be different because it's the line of events following different possible actions than the one I was in.

There are several models of time that would account for different effects.

The one I 'subscribe' to would mean that when you go back in time, it IS that time.
My explaination is going to such, but here goes;
When you go back in time, time continues from that point. If you killed your mother, you would still be there, but obviously you would not be born. When you go back in time you essentially transport matter back in time, there is no continuous connection.

To me this makes more sense.

I am sure that something would happen cause what if It was not ment for you to kill that person and you might pay for it later in the future..

My view on this is that the future takes into account travels into the past. Sounds strange, no? But the idea is that if you travel into the past you will not be able to change anything because your actions have already been taken into account in the future you will go back to.

In other words, you could not go back to kill your mother because your very existence makes this an impossibility.

This is a paradox that has confused people for years, I doubt we'll be able to really make sense of it.

This to me, is what I believe. Lets just say in the future, we do find a way to go back in time, How could it be possible though? According to the Law of Conservation, Matter doesn't get destroyed, nor made, it just changes forms, so if we go back in time, Matter will be changed to the form it was at that time, But just to you? If time travel does happen, scientifically, the whole universe will be brought back in time. You dont own your own matter, which if you could, would be like it would if time travel will be real. But matter is seen, and known by everyone, if one person tries to bring it back in time and change it, everyone sees it change, and then, in turn, goes back into time. That's what I honestly believe.

So, if time travel is possible and you change something, I guess it will change the future.

Physically, time travel IS possible. You see, when Astronauts fly out of orbit and into out space, they come back so fast that they actually travel backwards in time, but on a microscopic scale, less than 0.000001 Milliseconds. Thus meaning we would need to go so fast in outer space that we go back years, but how do we do so? Orbit around a black hole. How does it work? Simple. A Black hole is actually just an amazingly large build-up of mass, thus, being the heaviest mass with the strongest pull, orbiting it can send us flying in circles faster than the speed of light, but it only feels like a minimal speed to the astronauts. Thus, after re-landing on earth, they could be as far back as the 1970s from now in a matter of circling around a black hole maybe...6 times? Yeah, I know..It's crazy, huh?

Obiviously, yes if you do something big enough too.

If there was 2 people similar, and one asked a girl out, now lets say if I go back in the future, and asked the girl before the other guy, I think that pretty much explains itself.

Black Hole surfing for time travel. Sounds like a B movie scenario. I like it