Tilted Forum Project Discussion Community - View Single Post - Determinism vs The Uncertainity Principle

filtherton · 04-22-2007, 10:05 AM

archetypal fool,

I see what you're saying, i just disagree with you.

For instance, your reaction example isn't necessarily illustrative since the two C2 molecules would react with each other and the C1 molecule in theoretically predictable ways. We wouldn't necessarily be able to predict the ultimate outcome, but i hope we can both agree that it would conform to all known and unknown natural laws.

The universe can definitely be modelled using probabilities. I don't think that this is sufficient proof that the universe isn't deterministic. The validity of a probabilistic model doesn't necessarily imply that the phenomena being modelled is indeed random.

Think about a bridge over a highway. You're standing on this bridge and you're trying to figure out a way to understand why the particular cars appear when they do and where they do. You'd probably want to come up with some sort of predictive mathematical model. As far as you can tell, the cars show up with a completely random pattern. Now, for the purposes of the model you could assign a certain probability to the event where a specific make and model appears in a specific lane at any given time. You could base this probability on previous observation if you wanted. You would observe and refine your model and observe and refine your model over and over and over.

Now, eventually you could come up with a pretty complex probabilistic model describing the likelihood that a specific car will show up at a specific time. This model will no doubt effectively model the phenomena that is the highway as long as you keep to your initial assumptions because it is based on your observations.

The fact that you have a probabilistic model describing the appearance of cars on the highway doesn't mean that the phenomena of the cars appearing is random, it just means that as far as your model is concerned the appearance of the cars is random. That any one car should appear on the highway underneath your bridge is actually the direct result of a, most likely completely unremarkable, chain of interrelated events.

I hope this example illustrates what i see as a very important distinction between mathematical models of observed phenomena and reality. There is a small probability that i will go to sleep tonight and wake up on mars, but you can be sure that if i did wake up on mars it would be the direct result of a completely natural chain of events.

04-22-2007, 10:05 AM	#20 (permalink)
filtherton Junkie Location: In the land of ice and snow.	archetypal fool, I see what you're saying, i just disagree with you. For instance, your reaction example isn't necessarily illustrative since the two C2 molecules would react with each other and the C1 molecule in theoretically predictable ways. We wouldn't necessarily be able to predict the ultimate outcome, but i hope we can both agree that it would conform to all known and unknown natural laws. The universe can definitely be modelled using probabilities. I don't think that this is sufficient proof that the universe isn't deterministic. The validity of a probabilistic model doesn't necessarily imply that the phenomena being modelled is indeed random. Think about a bridge over a highway. You're standing on this bridge and you're trying to figure out a way to understand why the particular cars appear when they do and where they do. You'd probably want to come up with some sort of predictive mathematical model. As far as you can tell, the cars show up with a completely random pattern. Now, for the purposes of the model you could assign a certain probability to the event where a specific make and model appears in a specific lane at any given time. You could base this probability on previous observation if you wanted. You would observe and refine your model and observe and refine your model over and over and over. Now, eventually you could come up with a pretty complex probabilistic model describing the likelihood that a specific car will show up at a specific time. This model will no doubt effectively model the phenomena that is the highway as long as you keep to your initial assumptions because it is based on your observations. The fact that you have a probabilistic model describing the appearance of cars on the highway doesn't mean that the phenomena of the cars appearing is random, it just means that as far as your model is concerned the appearance of the cars is random. That any one car should appear on the highway underneath your bridge is actually the direct result of a, most likely completely unremarkable, chain of interrelated events. I hope this example illustrates what i see as a very important distinction between mathematical models of observed phenomena and reality. There is a small probability that i will go to sleep tonight and wake up on mars, but you can be sure that if i did wake up on mars it would be the direct result of a completely natural chain of events.