- #246
akvadrako
- 282
- 112
DarMM said:I think different axioms are different theories, if you have different fundamental base assumptions, I would view that as a separate version of MWI.
So if I had a theory which assumed ##a = b## and ##b = c## and proved ##a = c##, then I switched an axiom with the proof, would you call that a different theory?
I think it is a mistake to notice the extra assumptions and think this means they must not be claiming it is only the Hilbert Space + Unitary evolution part of QM. Unsubstantiated claims can easily be made, or people can view their assumptions as "obvious" or "trivial" details (or yet to be proved Lemmas), when in fact they change the physical picture.
If those assumptions change the physical picture, then they are mistaken; I think Wallace and Zurek would agree with that. The physical picture, at least the objective viewpoint of the whole system, should get all it's dynamics from unitary evolution. It doesn't even depend on decoherence. The additional thing which is needed, is some way to measure the system (not necessarily a particular way). Maybe it's so obvious it's overlooked, same as when numbers are assumed to be real instead of p-adic.
It's a common misunderstanding that WMI somehow depends upon a definition of world (or decoherence or branching structure). What defines WMI best is probably:
The further assumptions in the derivations are only used to show how a subjective agent within the WMI would experience it and if that would correspond with the Born rule. They are, as you said, (approximate) details for our convenience.DeWitt (1970) said:Without drawing on any external metaphysics or mathematics other than the standard rules of logic, EWG are able, from these postulates, to prove the following metatheorem: The mathematical formalism of the quantum theory is capable of yielding its own interpretation.
I do agree that's another widespread misunderstanding, which is what prompted me to respond to your claim that WMI has to derive the Born rule.DarMM said:This is also a widespread misunderstanding.