The easiest (although still not "easy") way to think about Time is literally as another dimension added to the visible 3 dimensions we all know and love. It does behave differently than the three visible dimensions, but the concept of how it interacts with us is similar.
It is not constant thoughout the universe, and it can only be measured by perspective. Here's how to think of the 4 dimensions:
All things travel at the speed of light, all the time. This is hard to conceive of at first, but much easier when you realize that such a speed is DIVIDED into the four dimensions, hence slowing down our overall progression.
If we travelled through a single dimension only, be it any of the 3 spatial dimension or the time dimension alone, we would be travelling at exactly 100% of the speed of light. But of course, we exist here and travel through all 4 dimensions simultaneously.
Therefore, think of it as such: each of the 3 spatial dimensions and the time dimension are represented by an empty glass. You have a full glass of water that represents you. In order for you to exist, you must spend energy in each of the dimensions in order to exist in their combined whole, so you pour 1/4th of the glass into each vial. Voila.
Now for the complicated part. Remember those experiments that proved the faster something moves, the more time slows down for that something? This is proven by the mere EXISTENCE of light. Light exists solely in the spatial dimensions, with no energy whatsoever spent in the dimension of time. Therefore, it travels at 100% the speed of light but NEVER AGES. Each particle of light in the universe is exactly the same age as it was when the universe was created. From it's perspective, time does not move at all, it does not even exist. The beginning and end of the universe will come and go, and the only thing light would know (if it were a conscious entity) from it's perspective is that it exists. It would not be aware that the universe ever had a beginning or an ending. It's 3 spatial cups were full allowing for maximum possible velocity, and time stands still.
Same applies to human, on a much lesser degree, but ALWAYS applies. The faster you move, the slower time goes from your perspective. The more still you are, the faster time moves. That's because when we move through the 3 spatial dimensions, we are pouring energy out of the Time cup, and into the 3 dimensions to allow us to move within them. Hence less energy in the Time cup, hence time is moving slower for us. If we sit still, very little energy is being expended in the spatial dimensions, therefore it is poured into the Time cup and time moves faster.
Of course, we do not notice this difference at all, since our perceptible speeds range from a mild walk to a few times the speed of sound. Compared to the speed of light, that's like watching from the vantage point of a bullet fired from a gun and trying to measure how fast a tree is growing. Even at several times the speed of sound, we are so far below light speed that the time differential between us and a stationary object is barely noticable. But the difference IS there.
Say two men born at exactly the same time were somehow garaunteed to die at EXACTLY the same age, right down to the minute. If one man were to spend his entire life running at a full sprint, and the other sitting in place, and they both lived to 100, there would probably be several minutes or so difference between the time they die. They would have no explanation for this other than the fact that time is indeed a personal variable based on energy spent within the 4 primary dimensions.
It has also been shown that the faster an object gets to the speed of light, the SMALLER that object becomes. Again this is to such a minute degree within our capable speeds that we cannot directly notice it. But for example, say two cars were measured to be exactly the same length while stationary. Now put them on a track that uses a stationary light sensor to measure the distance between the front and rear bumpers of the car while it is in motion. If one car were to travel a few kph, and the other to travel several times the speed of sound, the sensor would equate an inch or so difference between their sizes!
Ah the wonders of physics.
Sources used herein: Brian Greene - The Elegant Universe - Superstring Theory; Stephen Hawking - A Brief History of Time
Posted: Sat Apr 24, 2004 10:00 pm
