What is a computer model?
It is a process where you program a computer to simulate what you know about reality. Or to simulate how you think something might work.
For instance, you can program a computer to simulate the behaviour of a ball rolling down a ramp. Since you likely understand this quite well, your computer simulation will be extremely accurate and the behaviour of the virtual ball will very closely model the behaviour of a real ball.
This kind of model is usually useful for either educational purposes or for predicting the behaviour of things. That is, predicting behaviour which is very well understood but which the computer can model more efficiently then you would be able to by other means. Perhaps you could get a pen and paper, calculate what will happen and draw it out. But it is more efficient to program a computer to do this for you and tell you what might happen.
Perhaps you run a computer model of how an expensive jet engine might work. You want to try wrinkle out any huge flaws in your design before you go to the great expense of building a jet engine. This way you might be able to find out if it has any serious problems which might result in immediate and costly failure.
Or perhaps you can model how a building will perform under stresses or how an engine design will work under certain conditions. Things you probably could do by hand, but which are far more efficient to get a computer to do for you. It might be cheaper than building the wall just to do tests that can be done with some accuracy on your computer.
Is a computer model proof of anything?
No, it is not. A computer model simulates the behaviour of something. But it is still simply a computer program. It will only do what you tell it to do and no more. So, that means that the result of a computer model can only be as good as the programming put into it.
For a computer model to emulate the behaviour of something, the programmer must program in how he thinks that something should behave in various situations. He has to make assumptions or use prior knowledge about how that thing should act in those contexts.
This is the first way in which computer models can go wrong. The programmer’s assumptions have to be correct and what they know (or think they know) about the things they are modelling have to be correct. If the assumptions he programs into the model are wrong, then the results of the model will certainly be less than completely reliable.
But, even if all of their assumptions are correct, the results have to match reality. The program has to be able to produce the correct result. And the programmer must show that this is indeed the right result for it to be of any use.
Meaning that you already know the result. Or can at least check that the results you get are consistent with what you know to be true.
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