[FOM] Incompleteness and Physics: comment 2

[Vaughan Pratt]

Allen Hazen wrote:
> A similar proposal was made by Montague(1) to try to analyze the notion of a
> DETERMINISTIC theory: a theory is deterministic if, for any two
> mathematically standard models of the theory, isomorphism of the
> representations in the two models of the state of the physical world at one
> moment implies that they will have isomorphic physical pictures for every
> other moment of time. [...]
>
> Surely the possibility of a complete physical THEORY should not depend on
> whether the laws of nature are deterministic! [...]
> 
> Leaving a problem: how should one characterize the physical completeness of
> non-deterministic theories?

What's wrong with replacing Montague's requirement of isomorphism with 
bisimilarity, as standardly done in foundations of concurrency today?

Vaughan Pratt