[survivorboi]

So you fly along in your super man jet at the speed of light. Since no light can get to you because you're moving so fast, does everything seems to stop except for the light that already got to you? Kind of like when you're watching a movie and you press pause, everything stops except the scene that you stopped on. Because the lights that ALREADY got to you can't leave, while no other lights can get to you, right?

And what would happen to your watch?

One more question:

If you asked a friend to hold and flashlight and turn it on as soon as you run at the speed of light, what would you see? Would you even see that flashlight's light at all ? Or the light can't get to you?

[jcaron2]

One of the things that makes relativity so hard to understand is that all of those logical things you said are NOT true.

Let's say you're driving down the interstate in a car at 60 mph. If the car in the lane next to you is traveling in the same direction at 61 mph, you could look out your window and it would appear from your point of view like they were going only 1 mph (if you ignore all the road and background whizzing by at 60 mph!)

You can imagine the same would be true if you were somehow able to drive 1,000,000 mph, and the car next to you was traveling 1,000,001 mph.

So based on that logic, all of what you said above makes sense: If you could travel at light speed, the light itself would appear to be standing still and you'd get the "freeze-frame" effect.

However, light doesn't follow the normal intuitive "rules" that we intuitively understand. The thing with light is that no matter how fast you go, light which is approaching you will always appear to be traveling at light-speed from your point of view. Even if you're traveling in your superman jet at only 1 mph slower than the speed of light, the light that approaches you does not appear to be going only 1 mph (like in the car analogy). Instead, it would still appear from your point of view (usually called your "frame of reference" when talking about relativity) to be going 186,000 miles per second.

How can something catching up to you at only 1 mph appear to be going light speed? It happens by time slowing down. In your frame of reference time would still seem perfectly normal. Your watch would tick away one second in the same interval that you're used to. However, if you observed the world outside you'd see everything happening in extreme fast motion. For every second of time that passed by for you, you'd see thousands of years of time pass outside - the rise and fall of nations and civilizations and countless lifetimes. So it would actually look like the complete opposite of pressing the pause button - it would look like you hit fast forward.

As you get closer and closer to the speed of light, that fast forward effect gets more and more pronounced. If you could actually go the speed of light, time would pass by infinitely fast. From your frame of reference, absolutely no time at all would pass, not even a trillionth of the time it takes to blink your eye, but outside billions of years would pass by and the universe would meet whatever its ultimate end will be, taking you with it before you ever even knew what happened.

[survivorboi]

So what would I see if I live on another galaxy, the ones that are exceeding away from us almost at the speed of light? Ooh wait, if I somehow magically moved the another galaxy that is speeding away from the "Milky Way" galaxy, then when I'm on the other galaxy, the Milky Way would in turn exceed from me almost at the speed of light...

What would happen if I live on that other galaxy for, umm, a few seconds, then come back (magically, takes no time) to the Milky Way, would Earth be millions of years into the future or the past?

[survivorboi]

So if we could spin a machine at the speed of light, using some kind of super motor, we would create a time machine?

But then, how would we go to the PAST? Going at the speed of light would take us into the future...

[jcaron2]

You should read this wiki-book:

http://upload.wikimedia.org/wikibook...relativity.pdf