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Comment by robotresearcher | Hacker News Reader

> Theoretically all physical processes are predictable

If you count a radioactive decay event as a physical process, then this is not so.

I don’t. Radioactive decay is practically the very definition of the quantum effects I mentioned.

Seems a rather odd definition to make, then. Radioactive decay has large-scale effects, such as determining The elemental composition of the universe. Quantum effects govern the entirety of the universe, so I'm not sure why you would want such a large exception to your generalization.

I would go the other route. Nothing can be predicted, except statistically.

It's only odd if you're worrying about it outside of the context that the parent comment was talking about.

Which I wasn't. You clearly are. Yes, quantum stuff exists. At the scales the OP was talking about though they are mostly insignificant therefore I hand-waved them because they were not relevant to the discussion.

As far as I could tell, the thread started from the mention that Einstein believed that the universe is deterministic, which set the context of the thread. This argument is traditionally seen in context of quantum effects, and whether or not there exist hidden variables.

At the level of discussion in advanced physics, yes.

But that’s also because that’s where the really interesting work is.

It’s quite a different scope of conversation

Not counting radioactive decay as a physical process because you've chosen to define physical processes as deterministic is some intriguing mental gymnastics.

for the purposes described in the comment - I was quite clear that a certain level you get down to quantum effects.

But for the context of the physical processes the OP was talking about those effects are not significant and so I excluded them.

How about we replace the dice with Schrödinger's cat?

Then we’re dealing with a very different thing and the conversation is therefore different?

> Theoretically all physical processes are predictable, but in practice there is a limit.

So you defined away quantum effects as 'not physical', which most people would not agree with. How do feel about the theoretical limits on measurement accuracy that also negate your claim?

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