Re: Macroscopic Emergence in MWI worlds

--- In [email protected], Gary Oberbrunner <garyo@...> wrote:
>
> On Mon, Aug 19, 2013 at 11:55 AM, hibbsa <hibbsa@...> wrote:
> 
> > **
> >
> >
> >
> >
> > --- In [email protected], Gary Oberbrunner <garyo@>
> > wrote:
> >
> > >
> > > On Thu, Aug 15, 2013 at 11:56 AM, hibbsa <hibbsa@> wrote:
> > >
> > > > > The issue arises when you converge, on the one hand, the
> > > > requirements our own macroscopic world need to meet in order to be
> > > > consistent, reliable, repeating and ultimately deterministic. With, on the
> > > > other hand, the supposition all or most instances of quantum behaviour
> > > > involves or is associated with some emergence.
> > >
> > >
> > > If this is the issue, I'm not sure what the issue is. Emergence generally
> > > (not always, but mostly) smooths out low-level randomness or lumpiness into
> > > consistent, reliable, deterministic macroscopic behavior, which is what
> > > you're hoping for. Low-level quantum phenomena have lots of randomness;
> > > averaging over lots of those universes (or lots of instances in one
> > > universe) gives nicely predictable emergent properties like temperature,
> > > energy and entropy, or in another domain, predictable, stable giant ant
> > > hills from fairly random individual ant behaviors.
> > >
> > > ps: if you see this, it means I can post to FoR again.
> > >
> > > --
> > > Gary
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> > Gary, I think it's probably more reasonable to assume a lot more
> > emergence, in a lot more ways, than what might readily come to mind.
> >
> 
> Such as?
> 
> >
> > What is the problem. Well look, emergence is definitively independent of
> > the how the underlying quantum effects pan out. Which is the same as
> > saying, it's independent of the sort of variation produced by divergence.
> >
> 
> I'd say most emergent properties result from averaging large groups of
> properties.  (Not all of course; conscousness is possibly an emergent
> property of brains or other things.)  But yes, changing some minor property
> at the lower level typically has little effect on the macroscopic realm.
> "Butterfly effects" are the canonical counterexample, but they are
> comparatively rare.

if that's as far as it goes there's not a problem. In which case are you willing to provide a plausible description for how quantum divergence can become part of an effect that goes on result in macroscopic divergence. 
> 
> 
> > So the problem is, MWI has basically has no macroscopic influence.
> >
> 
> That I don't understand at all.  MWI just says the SWE describes physical
> reality, all of it.  Macro and micro.  MWI describes it all. 

You say MWI says that? I thought you said yesterday that's what gets assumed going in. In which case what the multiverse says is this might be what things would be like, *if* it was true.

Which backs off to the process that decided swe describes physical reality. Is there any mention why this is judged so important to be, reality would be willing to throw in a multiverse just to make it so? 

Isn't this going to end up back to observing all the baffling things that throw classical realism out the window? 

Doesn't that then become the starting point for why the swe must be a must have? 

 Maybe what
> you're saying is the details of particular interatomic reactions typically
> have no macroscopic influence.  True, as far as it goes.  If one photon
> goes off in this direction and another goes off in another, that rarely
> triggers vials of poison that kill cats.


> 
> 
> > I keep hearing about the bizarre vanishingly improbable outcomes, but
> > despite that saying nothing not already covered in probability/statistics,
> > it looks to me like mwi only works conceptually when applied to humans and
> > daft outliers.
> >
> 
> MWI by definition works when applied to physical objects - any or all of
> them.  I don't understand your comment above.  How does MWI not apply to a
> bouncing ball, for instance?  MWI says solve the SWE; we see that the ball
> is not relativistic so we can use Newtonian mechanics (which is a good
> approximation for slow, "regular size" objects).  We could in principle
> solve the whole SWE for the ball + rest of system, but it's computationally
> intractable (very).

I would have said the relevant question to the context would be whether divergence of the ball ever sees macroscopic divergence of the ball.  

> 
> 
> > Or please explain why I'm wrong. But please if you do, first say a few
> > words confirming what you think I think, otherwise I won't know if what you
> > are saying helps me :o)
> >
> 
> I'm not sure if you're wrong or not, since I don't understand your claim.
> (And even then who knows if I'd have the knowledge to say if you're wrong.)
> 
> >
> > p.s. there are other categories of major problem. What about the fact MWI
> > is created by integrating QM with a load of assumptions....that never get
> > any kind of treatment or analysis. Lots of implicit assumptions in there
> > too.
> >
> 
> Well, let's take one thing at a time.  But MWI is not created by
> "integrating QM with a load of assumptions".  It's defined by removing the
> collapse postulate and taking the rest (the SWE) as a description of actual
> physical reality (not just numerical fictions).  That latter is indeed an
> assumption that distinguishes MWIers from the "shut up and calculate"
> crowd, but they have no model at all for what is "real" -- they don't care
> as long as the math comes out.

If you want to throw out the local realism rationale for the swe thing, then it'd just become whatever reason goes in its place 
> 
> 
> > I think you, Deutsch, basically all of you, are seriously mixed up about
> > what you can and cannot do with unexamined assumptions in vague form
> > effectively treated as constants.
> >
> 
> You could be right.  What's an example of an unexamined assumption that's
> being treated as a constant?

- unless local realism gets treated in a process that explores what exactly is being suggested about local realism, and whether that can be better fitted. Then a process that establishes it thinks this is the only way local realism can be preserved in light of the quantum effects. 

Which presumably then has eliminated, for example, the scenario where local realism, space and time existed prior to the big bang, and are *re*emergent effects, and what QM is telling us is something about what it took for that sort of complexity to successfully reassemble after being broken down, and squirted through the needle of a camels eye. 

That would also preserve local reality in light of the quantum effects, but exchanging a through the camels eye puzzle for a multiverse. Maybe you would prefer the multiverse because maybe that feels like a solution not a problem. But on the other hand a through the camels eye problem is accessible via the scientific approach along many lines. And while the explanation leaves quantum mechanics still to be resolved, what it does do is point squarely the direction to where that solution will be found, and that will be the big bang

So, which is the better, more robust, more researchable, and overall more promising explanation. So more realistic by far because things get profoundly more realistic when something new is discovered, or equally promising, thrown out. 

 > 
> 
> -- 
> Gary
> 
> 
> [Non-text portions of this message have been removed]
>