[Arbite]

*snip*

The key point you missing here is that you cannot catch up to a beam of light. No matter how fast you travel, you will always measure the beam to be traveling at C. To an observer stationary relative to a fast object, he/she will see time pass slower in that object (some pretty basic trigonometry can actually show you by what factor this occurs, and it is commonly called the Lorentz factor). This is true for all observers, the ship would see people outside appearing to travel slowly providing the ship was a non accelerating reference frame. Basically, this means that time appears slower for those travelling faster than about .4c relative to an observer.



Also If a light beam was released from earth traveling at c, and a ship was approaching earth at .9c, standard logic would suggest that the ship would read the lights speed as 1.9c, but this does not occur, the ship still measures the speed as c.
I would recommend reading up on special relativity, it's not to difficult to grasp (apart from simultaneity). We covered it in what is the Australian equivalent of junior year highschool physics.

[Miracle Shooter]

I don't do time travel, but I put one of my characters through parallel universe travel and postulate how she would affect that parallel universe given that each one is unique. For example, she herself lived in a universe where she was a war orphan and was dumped into an alternate universe after getting caught in a funky blast from a lab (doesn't matter how she got there). She then has to travel the parallel worlds looking for her own, switching bodies with the her from that particular parallel universe, while the replaced consciousness ends up in her original body in her original world.

It's great fun, imagining her with parents, with friends, rich, poor, etc etc.

[Kilgore Trout]

I realize that this is widely accepted, but I've always thought that there was a little... "hole", so to speak, in this kind of statement. It's really rather hard for me to explain and it probably won't make any sense unless I could create an animation (might not even make sense then), but here goes nothing.

First off, a key (I'm going to try to make some sort of picture to help explain):

O = Earth
| = Light
: = Light from when you originally left Earth
/ \ = 1 day on Earth marker (alternates between / and \)
- = You
(Days on Earth will be counted as 3 lines of light, the third line being the marker)

Now, when you originally travel away from Earth at a speed close to light, let's say that you look out of a window in the back of your ship. It will seem as if time has slowed down, but really, you can't trust your eyes. Your eyes work by taking in light, but if you're travelling close to the speed of light, you'll just be moving alongside beams of light slowly passing you. This would cause you to see very little to no difference when you look at Earth.

[Day on Earth: 1 Day on Earth from your perspective: 1 ] O-
[Day on Earth: 2 Day on Earth from your perspective: 1 ] O||:-
[Day on Earth: 3 Day on Earth from your perspective: 1 ] O||\||:-
[Day on Earth: 4 Day on Earth from your perspective: 1 ] O||/||\||:-

What I'm trying to depict in that picture is simply that you're moving alongside the light.

Now, once you turn around and start heading back towards Earth near the speed of light, though, you'll see the light that was originally travelling behind you speed by you as you speed back towards Earth. I believe that time would almost appear to "fast-forward" as you travelled back to Earth until you finally make it back. This would be because instead of travelling alongside the light like before, you would now be travelling in the exact opposite direction of it causing it to speed by you as you speed by the light yourself, thus catching you up to Earth's time.

[Day on Earth: 5 Day on Earth from your perspective: 2 ] O||\||/||\-||:
[Day on Earth: 6 Day on Earth from your perspective: 4 ] O||/||\-||/||\||:
[Day on Earth: 7 Day on Earth from your perspective: 6 ] O||\-||/||\||/||\||:
[Day on Earth: 8 Day on Earth from your perspective: 8 ] O-||/||\||/||\||/||\||:

So I hope I didn't fail too much trying to explain that, though looking back at the "pictures" I made, it looks rather confusing. Regardless, the point I'm trying to make is that I believe that time is all about perspective. Take distant supernovas, for example. We know that they happened a very long time ago, but the light is just now reaching us. That doesn't mean that we're in the future or that supernova is in the past, does it? Light is our only means of deciphering time and with such a vast universe, it just isn't possible to create a single "here and now".

I'm going to stop before I begin to ramble, but I'd also like to say that I believe that time is completely set in stone, you aren't going to the future or to the past. I mean, really, it was thought up as a convenience. The idea that it's possible to manipulate something created in our minds is pretty absurd, in my opinion.

Also, one last thing. Sorry for any run-on sentences if there's any left in there, I'm horrible about those lol.

These may give you the answers you're seeking:

Physical Reality - Mathematics of Relativity

Time Dilation

And remember:

For Isaac Newton, a person could theoretically catch up to the speed of lightening, but Einstein believed this was impossible, because time progresses according to the reference point of the observer and how fast something moves, and nothing moves faster than the speed of light. For Isaac Newton, time was uniform and absolute, but for Einstein, time was relative. For example, astronauts feel weightless in space as they orbit Earth, because according to General Relativity, they are following the straightest possible path along the curvature of space-time. Isaac Newton, on the other hand, attributed this principle to gravity.

Einstein’s theory of Special Relativity applies only to special cases of motion under constant velocities instead of objects accelerating due to gravity. He realized, however, his theory was incomplete, because it did not involve gravity or acceleration. In response, he came up with the Equivalence Principle, which states, the effects of gravity are proportional to the effects of acceleration. Through this principle, astronomers began to think of space and time, not as separate, but rather as interwoven dimensions.

[Arbite]

In response, he came up with the Equivalence Principle, which states, the effects of gravity are proportional to the effects of acceleration. Through this principle, astronomers began to think of space and time, not as separate, but rather as interwoven dimensions.

I think the more correct term is indistinguishable from gravity. The equivalence principle is simple in that it states that if you are in a rocket ship traveling with a constant acceleration of 9.81m/s/s, and there is no contact with anything outside the ship, then there is no way for the observer on the inside to tell if the ship is accelerating in empty space, or simply sitting on the surface of the earth.

[Kilgore Trout]

I think the more correct term is indistinguishable from gravity. The equivalence principle is simple in that it states that if you are in a rocket ship traveling with a constant acceleration of 9.81m/s/s, and there is no contact with anything outside the ship, then there is no way for the observer on the inside to tell if the ship is accelerating in empty space, or simply sitting on the surface of the earth.

I agree; indistinguishable would be more accurate. I used the term proportional after I read The Essential Cosmic Perspective by Jeffrey Bennett and Parallel Words by Michio Kaku. I guess indistinguishable, for the Equivalence Principle, would imply a particular gravitational field being indistinguishable from an inertial force, which affects the body’s non-inertial frame of reference. The non-inertial frame of reference does not have constant velocity, because it is accelerating.

In other words, gravity accelerates all objects equally, despite their masses/structures.

[Ryan]

All the time - ever watched Heroes? Watch it!

[Cheveyo]

All the time - ever watched Heroes? Watch it!

Heroes was so disappointing. It spent it's whole time almost getting good. It would reach that almost peak and then start to suck once more.

[Ryan]

Heroes was so disappointing. It spent it's whole time almost getting good. It would reach that almost peak and then start to suck once more.

I totally agree. And the fact that the directors seemed to have totally forgot the material in the previous seasons... it was overall pitiful if one was to analyze it. But if you were simply using it to escape into a world of fantasy, powers, time travel, love, etc.... oh it was wonderful.

[Mysteriouschic]

I've always been like that. My mind is constantly in the future imagining what life will be like or I'm in the past wondering if I'd do something a different way if I could go back in time or even if I was another person what would I be like . Or even going back in time changing something or even in a different decades if I was born in the 80s would I be the same. I also think about the whole science theory of time travel
I'm never in the present now. I love travelling I've only been to a few places. But I'm constantly thinking wondering what other places of the world are like . I have list in my head of where I want to go. I think too far ahead .

[Custers Last Band]

I was curious, do any of you daydream about traveling to the past, or to the future?

I just did this tomorrow! And in all probability I probably will yesterday too.