## Explaining determinism

One thing I liked about a classical mechanics lecture by Leonard Susskind was that he pointed out that you would need infinite precision for a system to be deterministic (if you are +/- some tolerance on a measurement, your deterministic classical mechanics will not give you the correct next state of a system). That alone makes it sound impossible for determinism to be accepted, since we would need to approach infinitely small measurements of position.
 I disagree. I think you would need infinite precision to take advantage of a deterministic universe, not for it to exist.

 Quote by the_emi_guy QM is non-deterministic. The point was that even ignoring QM and assuming we lived in a deterministic world (which we do not), chaos theory still presents a significant barrier to making certain predictions. We may need to measure initial conditions with infinite accuracy, which is not possible.

Wrong Qm is not indeterministic, only the measurements. If you have a tenseless theory of time then determinism is true even for the copenhagen interpretation since the observer and his measurements, and the electrons behavior-- all are predetermined to have happened.

The extent to which the human mind is able to make predictions is irrelevant to determinism.

Now to the question posed. You could explain to your friend that determinism is the same as thinking of being in a movie were the beginning and end already exist and your actions in the movie also as much determined as anything else in the film.

Determinism thus has no bias towards causality per ce but simply that all events that occured- had to happen, and had to happen they way they did and that there is a future written in stone. Wheter there are quantum events happening without a cause is irrelevant to determinism.

People claiming that QM is ontologically indeterministic are ignorant of the fact that time as we perceive it is an ILLUSION.

 Quote by 1MileCrash I disagree. I think you would need infinite precision to take advantage of a deterministic universe, not for it to exist.
When I say measure, that can be taken in the context of lab measurement, but also in the context of natural systems interacting with each other.

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 Quote by rocket123456 Wrong Qm is not indeterministic, only the measurements. If you have a tenseless theory of time then determinism is true
This is wrong. QM is fundamentally indeterministic. It is impossible to know an object's position and momenta exactly within QM.

 Quote by Vorde This is wrong. QM is fundamentally indeterministic. It is impossible to know an object's position and momenta exactly within QM.

Again I am referring to ontological indeterminism.

Determinism is true for the world regardless of if you can make accurate predictions.

A hypothethical alien that could take the measuring effect into account would be able to make predictions like laplace demon as Hawkings pointed out. Or take a different example a person with 100% fool proof precognition abbilites, this individual would be able to know all future events.

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 Quote by rocket123456 Again I am referring to ontological indeterminism. Determinism is true for the world regardless of if you can make accurate predictions. A hypothethical alien that could take the measuring effect into account would be able to make predictions like laplace demon as Hawkings pointed out. Or take a different example a person with 100% fool proof precognition abbilites, this individual would be able to know all future events.
Two things, you are still wrong.

Precognition doesn't exist, that arguement is invalid.

The measuring effect isn't the problem with QM, the uncertainty principle is, look up the difference.

 Quote by Vorde Two things, you are still wrong. Precognition doesn't exist, that arguement is invalid.

Yes it does and it has been proved many times in experiment. The science community does not want to hear about it.

It does'nt matter if however precognition were not to be possible, just imagine an alien with powers to view into the future.. would he be able to see future events in this universe??

Well if you believe in the tenseless theory of time, the alien would be able to see the future since it already exist.
 Recognitions: Gold Member Okay, you've stopped arguing with science, and I'm going to stop trying to help someone who refuses to be helped.