Re: Macroscopic Emergence in MWI worlds

--- In [email protected], Gary Oberbrunner <garyo@...> wrote:
>
> On Tue, Aug 20, 2013 at 4:59 AM, hibbsa <hibbsa@...> wrote:
> 
> > **
> >
> >
> > --- 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.
> >
> 
> Good.
> 
> 
> >  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.
> >
> 
> I don't know.  What is "quantum divergence"?  Is it just that in some
> worlds the photon is emitted at t_1, and at some others at t_2?  It's not a
> term I'm familiar with.
>

the term wasn't correct, but we had a context and there was a key work divergence. I was talking about divergence in the multiverse. 
> 
> 
> > > > 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.
> >
> 
> Sorry, perhaps I missed something.  MWI is the theory that the SWE is a
> description of reality, and its observables are real (they exist, not just
> as "convenient mathematical fictions").  I.e. there is no collapse.
> 
> 
> > In which case what the multiverse says is this might be what things would
> > be like, *if* it was true.
> >
> 
> I'm not sure how to parse that.  I'm not sure the multiverse "says"
> anything, especially anything self-referential.

Gary, I was using the same style you had just used to me, you said "MWI says..." 

 
> 
> 
> >  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?
> >
> 
> That last part doesn't seem to be a complete sentence.  I'mt sure how to
> parse it.  Nor am I sure how to parse the first sentence fragment, though
> there I'm guessing you mean "this [foregoing] raises the question of what
> process was used to decide that the SWE describes physical reality".

Dude, in the previous  gone you had said MWI didn't come out of a process involving assumptions, including for local reality. You seemed to want to place the swe as the seed motivation. I 

> 
> It's clear that the SWE correctly predicts the outcome of physical
> processes and experiments, to a very high degree of precision.  That is to
> say, it's probably not wrong in its domain of applicability.  The "shut up
> and calculate" folks have been using it very successfully for satellite
> design, GPS, and lots of other applications.  Your question appears to be
> about whether we should "take it seriously" as describing ontologically
> real things, specifically the part of it it says that any given interaction
> has multiple outcomes, rather than the one we're used to.  This is a harder
> question of course.  There are several competing interpretations of QM.  I
> think most serious physicists no longer think the Copenhagen interpretation
> (instantaneous collapse) describes reality, so what your question boils
> down to, I think, is: do any of the current interpretations of QM describe
> reality?  If so, which one?  If not, where might we look?  I'm afraid I
> don't have much to offer on that topic.  The SWE does such a good job that
> I think QM describes reality.  Collapse seems so obviously bad that
> Copenhagen is out.  That leaves violating locality (no FTL travel), or
> causality (as commonly construed), or "realism", that events have only one
> continuer.  I favor the latter, which is MWI, because the others seem to
> cause more troubles, and I'm reasonably comfortable with the main difficult
> idea of MWI, that the world is a lot bigger than we thought -- it's
> happened repeatedly throughout history.
> 
> >
> > Isn't this going to end up back to observing all the baffling things that
> > throw classical realism out the window?
> >
> 
> Again I'm not sure how to parse that sentence.  What is the "this"?  And
> what are the "baffling things"?  And of course "classical realism" (by
> which I assume you mean a Newtonian block universe) isn't even close to the
> window anymore, it was gone nearly a century ago.
> 
> >
> > Doesn't that then become the starting point for why the swe must be a must
> > have?
> >
> 
> I'm not sure what such a starting point would be.  My starting point for
> "why the swe must be a must have" is that it does an astoundingly good job.
> 
> 
> > 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.
> >
> 
> I don't know what that sentence means.  What is "divergence of the ball"?
>  And how does divergence "see" anything?  Maybe if you explain what
> "divergence" is I'll get it.
> 
> > > 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
> >
> 
> Local realism is not a rationale for "the swe thing" -- the SWE is what it
> is.  If you don't add the collapse postulate, you get something that is
> local, but not "realistic" (single-valued) - i.e. MWI.  If you throw out
> locality, you can add collapse or various other things.  And so on.  None
> of these are rationales for SWE, they're consequences of it.  What you
> can't have is the SWE plus local realism (and causality as usually
> understood).  It's internally inconsistent.
> 
> (I don't want to go off on a tangent, but I'll reiterate my common refrain
> that "realism" as a QM term meaning single-valued is emotionally loaded
> [who would want an UNrealistic theory??] and not even correct.  The MWI is
> perfectly "realistic" in the common sense; that's why I prefer to use
> single-valued instead.  Someone else here recently suggested another term
> for it, which I can't remember now.)
> 
> > > > 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.
> >
> 
> Your first sentence is incomplete.  I have no idea what it means, nor if
> it's an answer to my question.  Your second sentence is English but I still
> can't make sense of it.  How does a process think?
> 
> > 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.
> >
> 
> Since I couldn't parse the sentence before this, I don't understand the
> "which" (first word).  And I'm not sure what any of this has to do with
> before or after the big bang.  And of course I don't think "local realism"
> is possible at all in a QM world.
> 
> 
> > That would also preserve local reality in light of the quantum effects
> >
> 
> Sorry, what would preserve this?
> 
> 
> > , but exchanging a through the camels eye puzzle for a multiverse.
> >
> 
> I don't really understand the "through the camels eye puzzle".  I have a
> vague feeling you are trying to convey something about information transfer
> during the big bang, but I'm not sure what it is or why it's relevant.
> 
> > 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
> >
> 
> Sorry, what is the explanation which points in that direction?  (And what's
> it an explanation of?)  I missed that.
> 
> 
> > So, which is the better, more robust, more researchable, and overall more
> > promising explanation.
> >
> 
> I assume that's a question despite the period.  Unfortunately I don't know
> what the two explanations being evaluated are.  I assume one is QM and/or
> one of its interpretations.
> 
> 
> > So more realistic by far because things get profoundly more realistic when
> > something new is discovered, or equally promising, thrown out.
> >
> 
> Again, I'm not sure what that sentence fragment refers to, nor its meaning.
>   Sorry.
> 
> -- 
> Gary
> 

Gary - You're a good guy and we're comfortable. It's up to you of course, but if you find yourself at the end of a reply to me, and pretty much every one of your responses is saying you don't parse this, or you don't see the point, and so on. Unless there's some burning reason that you want to keep running the thread, feel free to choose to discard before sending :O)