Quote:
Originally Posted by modest
I think a good example of change is radioactive decay. For example, if we have a sample of carbon and we measure how much carbon-14 is in it then we can predict how quickly the C-14 will turn into nitrogen. It's a very basic process in nature that happens at a predictable rate. One gram of C-14 will be half a gram in 5730 years.
So, change is a good word to describe what's happening. Certainly carbon is changing into nitrogen via beta decay. But, change is incomplete. It doesn't completely describe the situation. Saying one gram of C-14 changes into a half a gram of C-14 is not the whole story. For the whole story we have to say how quickly it changes, how much time it takes to change.
So, it's not so much that time 'drives' change. It's more that change is meaningless without time. Consider change in position. Let's say there is a ruler that is one meter long lying on a lab table. We roll a ball from the zero position to the 100 centimeter position. So then: Change = 1 meter I wouldn't say time drove that change or caused that change. But I would say there is no way to discuss how fast the ball went without a very real process of the universe called time. Speed is change in position divided by change in time. If it took the ball one second to change position then the ball moved at one meter per second.
Change requires both space and time - two dimensions. It is impossible to describe change without both. So, time is not just a human concept. It is a human concept that describes something real about the universe.
~modest |
You make good points. Especially about change being meaningless without time to describe it and I think I agree with you completely. Time is our way of understanding and giving meaning to change. The 'something real about the universe' is that change appears to be constant and one kind of change can be compared to another kind of change. That implies that all changes have a common cause, a common motive force.
The laws of physics are our identifications of how things act. Whether it's regarding motion or mass or chemical reactions or radioactive decay, what would be wonderful is to find a common cause for all of it. So far we haven't. Time has been the placeholder for the cause.
The ingenuity of man is such that we can work with flawed theories and don't need to change them as long as they work. When they don't work, then we change them. There really isn't much impetus to change when we can work within our current framework.
If there is value in this discussion, it's in questioning the concept of time - a very important part of our current framework. Personally, I think it stops us from seeing change in a different light. It takes an act of will to step outside our framework and consider change without time associated with it or at least to consider the cause of change that way.
Let's assume two things for the sake of argument. 1. there is a common cause for all changes. 2. that change is constant.
The problem with lumping all changes together in my previous statement is that there seems to be two kinds of changes that might not be related: changes in material structures and changes in position.
The concept of time allows us to bring these two kinds of changes together under its umbrella. Perhaps that has clouded our understanding. If we take 'time' out of the focus, we have two kinds of changes to account for and perhaps it's an easier starting point.
What if we say that chemical reactions and motion have nothing in common? Ultimately they might, but for now why not assume they don't. Just for grins. It could be that all motion was initially caused by a chemical reaction. That would make all change, including positional changes, relative to physical structural change. And for the moment, let's leave 'space' out of the focus too as it might muddy the waters so to speak.
Ok then, what drives chemical reactions? What drives change to take place at the smallest levels? What makes an electron fly around the nucleus of an atom? What is driving that stuff if it isn't time?
If everything that takes place happens because our universe started with a big bang, it would seem that the total 'energy' in the universe would be constant and would eventually run down and stabilize (assuming that all matter attempts to reach a state of equilibrium). Why hasn't it? Or are we operating on the assumption that it is running down? What if it isn't? Then we'd need to know where the motive force is coming from and what is driving the universe of change.
If it's not time and it's not magic, what is it?
