Monday, April 4, 2011

Back to Time

I have not been on this blog thing, for a long time. At request, I am half forcing myself to put something up. I would like to thank the individual who prompted me to do so, for they are awesome.

My excuse for not being on is the usual, see other posts for excuses.

Have you ever tinkered in time dilation? The concept regarding traveling at very high speeds, close to the speed of light. The closer you travel to the speed of light (if you start below or above, but for simplicity sake we'll assume we're looking at what travels under the speed of light), the slower time moves around you. The answer to this is surprisingly simple. I think I've made note of it on this blog before, but this post will be devoted to it.

Physics, it's for the win.

First of all, we have to consider the speed of light, c. Light travels at 3.00x10^8m/s, no matter your frame of reference. This is a bit counter intuitive, but true. Normally something may appear to move 10m/s, but if you are moving in the same direction at 7m/s, it will appear to move at only 3m/s. Your perspective changes how you see the speed. No matter how fast you move, light appears to move at the same speed, c.

To maintain this, light must have some odd characteristics. One of them is it may slow time down if needed. The only time this is needed, is when someone is moving close to the speed of light. In clasical physics, if you move close to the speed of light and you are assuming the speed of light is not fixed (it changes with perspective, rather than maintaining it's speed), light should appear to not be moving or it would be moving very slowly. Just as in our 10m/s thought experiment, we should be able to slow light down by moving close to it's speed. I feel like I'm rambling and repeating myself, so this might be a bit jumbled.. I think I have my point across?

Light always goes at the same speed, no matter how fast you are moving. The characteristic of time slowing down to maintain this is needed so we do not 'slow down light' by moving quickly. If it did not do this, physics would break. Yes, that is a good, simple explanation.

Now you may be able to see where this is going. Rather than the 'm' in meters per second slowing down, the 's' does. Velocity is measured in m/s. Lets do some math.

You move a displacement of 100 meters in 10 seconds. Your velocity is 100m divided by 10 seconds, or 10m/s (10 meters traveled, per second).

Now, if we increase this to 150 meters in 10 seconds, our velocity is now 15m/s.

Lets assume the speed of light is limited at 101m/s though, so when we get to 100m/s it is needed for time and/or light to 'slow us down' somehow. As we try to increase the speed, the energy goes towards slowing down the time. Instead of 100m being traveled in one second, the same distance is traveled in two seconds.

Now there is not a doubling of time, at least with numbers like this. Keep in mind these are just demonstrations with no relation to actual numbers. Two is just an easy to work with, when we started with one.

Another way to look at it is as this:
100m divided by 10s is 10m/s.
100m divided by 20s is 5m/s.
The distance traveled is equal to what was traveled original, but it takes more time now. We do not observe a change in a distance, but we do observe the change in time.

Bugworlds - I'll probably be far away from my blog until I'm prompted again.