at least tangentially P-related: Class of all classes

[David Payne]

Monte wrote:

> Laplace's speculation c. 1800 that if
> we knew the mass and position and velocity of every particle in the
> universe, we could use mathematical physics to run the movie forward or
> backwards at will; that data would specify the whole history of the
> universe

This seems correct (though it flies in the face of free will), but in order to do this, it seems to me that we would need a computer the size of the universe (since our computer cannot be made of particles smaller than those of the universe), and our computer would have to operate (i.e., make predictions) in real time (since the movements we are predicting are already operating at the fastest possible speeds). It would be like Borges' real-size map ...

No? Am I missing something? Any attempt at compressing the file might drop some key piece of info (e.g., a butterfly flapping on the other side of the planet), right?

Does this answer Laura's question?

> Does this mean that chaotic systems are not inherently chaotic, but appear so to us because we don't have "initial data precise and fine-grained enough to capture every flap or no-flap"?
> You say we can never have the precise data, but is the "never" implied in the definition of a chaotic system, or could precise data be technologically attainable (in theory, if not practice)? If so, wouldn't chaotic systems be reduced to deterministic?

Assuming that there was a chaotic system that operated independently of the rest of the universe, we would need a computer the exact same size and speed as that system in order to account for all the interactions, thereby rendering predictions impossible (since predictions require faster than real time calculations).

Surely I'm overlooking something?

(Thanks, BTW Monte, for mentioning Laplace. What a Pynchion name! I hadn't heard of him and will have to learn more.) 

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