[ExI] Models vs. Reality

[scerir]

Lee Corbin:
> Yes, when I refer to the "state of a quantum system", then
> of course I am aware that it's the "quantum state" that we 
> wish to talk about. But when I ordinarily refer to the *state*
> of a system, I mean the state or situation OF THE SYSTEM.
> Don't you?

Yes. And no. Unless you follow one of those ontological 
interpretations of QM (de Broglie - Bohm; MWI; Weak Measurements,
etc.) also the meaning of 'quantum state', or the meaning of
'state of a quantum system', has much to do with the *situation* 
of a larger system (preparation of the quantum in a certain state; 
detection of the quantum in a certain state; the quantum itself).
Here,ie, you may find a description of these intricacies ...
http://www.arxiv.org/abs/0705.2144

s.

"It was tacitly assumed that measurement of an 
observable must yield the same value independently 
of what other [say 'compatible'] measurements may 
be made simultaneously [....]. There is no apriori 
reason to believe that the results should be the same. 
The result of an observation may reasonably depend 
not only on the state of the system (including hidden 
variables) but also on the complete disposition of 
the apparatus [...]".
-John Bell, (Rev. Mod. Phys., 1966)