Re: MWI

--- In [email protected], Bruno Marchal <marchal@...> wrote:
>
> 
> On 27 May 2013, at 14:32, hibbsa wrote:
> 
> > Does this question an answer?
> >
> > Is it logically possible for the multiverse to produce macroscopic  
> > universes exhibiting any statistically significant differences than  
> > our own universe?
> >
> > I mean "statistically significant" in the most rounded possible sense.
> >
> > - Any difference that our universe couldn't have gone the way of,  
> > consistent with its initial conditions all laws of physics assumed  
> > constant
> >
> > - Any difference in terms of any phenomena existing at any level of  
> > abstraction in greater or lesser or with any difference in any  
> > attribute including (a) abundance (b) probability of occurrence (c)  
> > relation with other phenomena (d) internal constituents.
> >
> > - Any difference on any level at all where to be different at the  
> > bottom level requires contradicting the probabilistic rules of QM  
> > and/or causing unique consequences of those rules as a result of  
> > interaction with macroscopic phenomena and at the top level requires  
> > any significant difference in the timing, macroscopic and  
> > microscopic structure, and ultimate fate of the universe.
> >
> > The reason I think this question deserves a proper full answer. And  
> > by that I mean...not just a criticism of the way the question is  
> > formed is because there could be important consequences...which may  
> > not be worked through. And the philosophy is all about intrepidly  
> > working through the consequences?
> >
> > I've got some consequences waiting for your criticism. But I think  
> > it's important to establish your criticism or acceptance of the  
> > above first.
> >
> 
> What do you mean by "exhibiting any statistically significant  
> differences than our own universe? "
> 
> If you prepare an electron in the up + down state, and if you measure  
> its up/down state, QM predicts that you will end up yourself in the  
> "seeing-up + seeing-down" state. If you had decided to go in the North  
> or in the south, according to the result of that measurement, you end  
> up in the visiting-North + visiting-South. from your points of view  
> that is statistically different, imo. You get two macroscopically   
> quite different lives. This with a probability 1/2, when evaluated  
> before the measurement, about your future first person points of view.
> 
> Now if your question is just "is there a macroscopic world in which  
> elephant can fly?", the answer is also "yes", but the probability,  
> here-and-now, that you will see such an elephant is equivalent to  
> winning the big lottery every second for a time much bigger than the  
> age of the universe, so don't count on it. Near death, that question  
> is just much more complex to get an answer today.
> 
> The MWI is just the statement that the SWE applies to everything,  
> macrosocopic, mesoscopic, microscopic, etc.
> 
> OK?
> 
> Bruno
> 

Hi Bruno - no not OK but my fault. I meant statistically different macroscopic universes. So you need to name your macroscopic object...preferably with clear, known emergent properties. And show how those emergent properties are altered in any of its associated quantum histories, from say,....the differences that would be exhibited by enough copies of the object in this universe to represent all the possible quantum histories. 

And if there aren't any differences...and if our macroscopic world is emergent phenomena from the quantum state, then it's hard to see how the multiverse can exhibit statistically significant differences between its macroscopic universes.