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Indeed - and one can eliminate determinism without resort to QM: Classical mechanics is also indeterministic, you just have to know where to look. Read "Causat

Indeed - and one can eliminate determinism without resort to QM: Classical mechanics is also indeterministic, you just have to know where to look. Read "Causation as Folk Science" by John D. Norton [1]. He sets out a very simple example of a classical system that behaves indeterministically, analogous if not in fact homologous to how the radioactive decay of a single particle cannot be predicted. The apparatus to demonstrate this consists of a dome with a particular curve (see the paper for details). A sphere placed at the apex of the dome will eventually roll off, in a random direction. But we can predict NEITHER when NOR which direction. And yet it is a fully defined classical system. (And see [2], recently discussed here, to see how relevant and frutiful classical mechanics remains to this day.) (Note that a better word than indeterministic might be acausal, which is the word Norton uses when describing the dome. Either way, one need not resort to QM, regardless interpretation, to demonstrate that determinism does not in fact prevail in our universe. We can all behave in ways that are not predetermined.) [1] http://www.pitt.edu/~jdnorton/papers/003004.pdf http://www.pitt.edu/~jdnorton/papers/003004.pdf [2] http://arstechnica.com/science/2014/08/the-never-ending-conundrums-of-classical-physics/ http://arstechnica.com/science/2014/08/the-never-ending-conu...

lutusp 12y ago
> Classical mechanics is also indeterministic, you just have to know where to look. On the contrary, classical (pre-quantum) mechanics is certainly deterministic. The first real challenge to a strict relationship between causes and effects was QM, which (as you may recall) caused Einstein to begin a long campaign against those ideas -- "God doesn't throw dice," and so forth. > But we can predict NEITHER when NOR which direction. Our inability to predict an outcome doesn't constitute an argument against determinism, only the limits of experimental measurements. > analogous if not in fact homologous to how the radioactive decay of a single particle cannot be predicted. That's simply false. A radioactive decay's timing is certainly nondeterministic, but the direction an observed, macroscopic ball takes is deterministic, even if we don't get the memo. Think a bit harder. If Norton could demonstrate the indeterminism of classic mechanics, as opposed to publishing a philosophical paper on the topic, he would win a Nobel prize for undermining a well-established physical principle. But philosophy isn't science. > We can all behave in ways that are not predetermined. We can all behave in ways that we believe to be nondeterministic, but free will remains an open philosophical question.
- PeterWhittaker 12y ago
  Our inability to predict an outcome doesn't constitute an argument against determinism, only the limits of experimental measurements. I'm not sure how to square that statement with the paper: The paper does sets the equations of motion for an object, equations that completely define the objects motion, but that cannot predict when the object will move. This has nothing to do with the quality of measurement.

lutusp 12y ago

> Classical mechanics is also indeterministic, you just have to know where to look. On the contrary, classical (pre-quantum) mechanics is certainly deterministic. The first real challenge to a strict relationship between causes and effects was QM, which (as you may recall) caused Einstein to begin a long campaign against those ideas -- "God doesn't throw dice," and so forth. > But we can predict NEITHER when NOR which direction. Our inability to predict an outcome doesn't constitute an argument against determinism, only the limits of experimental measurements. > analogous if not in fact homologous to how the radioactive decay of a single particle cannot be predicted. That's simply false. A radioactive decay's timing is certainly nondeterministic, but the direction an observed, macroscopic ball takes is deterministic, even if we don't get the memo. Think a bit harder. If Norton could demonstrate the indeterminism of classic mechanics, as opposed to publishing a philosophical paper on the topic, he would win a Nobel prize for undermining a well-established physical principle. But philosophy isn't science. > We can all behave in ways that are not predetermined. We can all behave in ways that we believe to be nondeterministic, but free will remains an open philosophical question.

PeterWhittaker 12y ago
Our inability to predict an outcome doesn't constitute an argument against determinism, only the limits of experimental measurements. I'm not sure how to square that statement with the paper: The paper does sets the equations of motion for an object, equations that completely define the objects motion, but that cannot predict when the object will move. This has nothing to do with the quality of measurement.