Oh, I forgot my main problem with QTI :-)
Basically it's to do with the rate at which decoherence spreads (presumably at the speed of light?) and the finite time it takes
someone to die. So if you were shot (say) the QTI would predict that there was some point in the process of your body ceasing to
operate at which some unlikely quantum processes separated branches of the multiverse in which you died to ones in which you
remained alive (forever, presumably). The problem is working out exactly where that happens (I suspect it gets worse if you include
relativistic considerations).
Another question is what happens in cases of very violent death, e.g. beheading. After someone's head is cut off, so they say, it
remains conscious for a few seconds (I can't see why it wouldn't). According to QTI it experiences being decapitated but then
survives indefinitely - somehow . . . well, I'd like to hear what QTI supporters think happens next (from the pov of the victim).
Are they magically translated into a non-decapitated version of themselves, and if so, how? Surely it can't be in the same quantum
state that they're in? If not, do they experience indefinitely continued survival as a severed head, or . . . what??? Just curious!
Charles
> -----Original Message-----
> From: Charles Goodwin [mailto:cgoodwin.domain.name.hidden]
> Sent: Tuesday, 4 September 2001 1:42 p.m.
> To: everything-list.domain.name.hidden
> Subject: RE: FIN too
>
>
> Um, OK, I don't want to get into an infinite argument here. I
> guess we both understand the other's viewpoint. (For the record: I
> don't see any reason to accept QTI as correct, but think that
> *if* it is, it would fit in with the available (subjective)
> observational evidence - that being the point on which we
> differ. I also think that for QTI to be correct, a number of
> other things
> would have to hold - space-time would have to be quantised,
> objects in the same quantum state would have to be literally identical
> (no matter where they happened to be in the uni/multiverse) .
> . . and, either the multiverse has to exist, or our universe has to be
> infinite . . . and probably a few other points I can't think
> of right now!)
>
> Charles
>
> > -----Original Message-----
> > From: Jacques Mallah [mailto:jackmallah.domain.name.hidden]
> > Sent: Tuesday, 4 September 2001 1:12 p.m.
> > To: everything-list.domain.name.hidden
> > Subject: RE: FIN too
> >
> >
> > >From: "Charles Goodwin" <cgoodwin.domain.name.hidden>
> > >[Jacques Mallah wrote]
> > > > But there's one exception: your brain can only hold a
> > limited amount
> > >of information. So it's possible to be too old to remember
> > how old you
> > >are. *Only if you are that old, do you have a right to not
> > reject FIN on
> > >these grounds.* Are you that old?
> > >
> > >Yeah, that's one of my objections to QTI. Although perhaps
> > add-on memory
> > >chips will become available one day :-)
> >
> > OK. (And even if the chips become available, you'd
> > probably only be
> > able to add a finite # before collapsing into a black hole.)
> >
> > > > Right. Do you think you are in an infinitesimal
> > > > fraction, or in a typical fraction?
> > >
> > >Infinitesimal, if QTI is correct, otherwise fairly typical.
> > Assuming QTI is
> > >correct and ignoring any other objections to it, it's
> > *possible* for me to
> > >be in an infinitesimal fraction - in fact it's necessary.
> >
> > Right - which is why Bayesian reasoning falsifies FIN,
> > but only with
> > 100% reliability as opposed to complete reliability.
> >
> > >but according to QTI I *must* pass through a phase when I
> > see the unlikely
> > >bits, no matter how unlikely it is that a typical moment
> > will fall into
> > >that phase. Even if I later spend 99.9999999999999999999....% of my
> > >observer moments seeing the stars going out one by one,
> > there still has to
> > >be that starting point!
> >
> > Right, again, that's why the reliability is just 100%.
> >
> > >My (ahem) point is, though, that none of us ARE at a typical
> > point (again,
> > >assuming QTI). In fact we're in a very atypical point, just
> > as the "era of
> > >stars" might be a very atypical point in the history of the
> > universe - but
> > >it's a point we (or the universe) HAVE TO PASS THROUGH to
> reach more
> > >typical points (e.g. very old, no stars left...). Hence it's
> > consistent
> > >with QTI that we find ourselves passing through this point...
> >
> > Right, consistent with it but only 0% of the time, hence
> > the Bayesian
> > argument is to put 0 credence in the FIN rather than strictly
> > no credence.
> >
> > >I'm not arguing for QTI here, but I do think that you can't
> > argue from
> > >finding yourself at a particular point on your world-line to that
> > >world-line having finite length, because you are guaranteed to find
> > >yourself at that particular point at some (ah) point.
> >
> > Right, which is why I'm (now) careful not to make *that*
> > argument by
> > arbritarily using one's current age to base a reference point
> > on. (e.g. in
> > my reply to Bruno.) Rather, I argue that from being at a
> > point prior to
> > some _natural reference point_ such as the "can calculate my
> > age" crierion,
> > one can conclude that one's world-line is finite.
> >
> > >So I'm rejecting, not Bayesian logic per se, but the
> > application of it to
> > >what (according to QTI) would be a very special (but still
> > allowable) case.
> >
> > There are no grounds to reject it in this case, since
> it would be
> > reliable almost all of the time. There's no difference
> > between using a
> > method because it works for most people vs. using a method
> > because it works
> > for me most of the time. At any given time, it works for
> > most people, too.
> >
> > >The basic problem is that we experience observer moments as
> > a sequence.
> > >Hence we *must* experience the earlier moments before the
> > later ones, and
> > >if we happen to come across QTI before we reach "QTI-like"
> > observer moments
> > >then we might reject it for lack of (subjective) evidence.
> > But that doesn't
> > >contradict QTI, which predicts that we have to pass through
> > these earlier
> > >moments, and that we will observe everyone else doing so as well.
> >
> > >I wish I could put that more clearly, or think of a decent
> > analogy, but do
> > >you see what I mean? Our observations aren't actually
> > *incompatible* with
> > >QTI, even if they do only cover an infinitsimal chunk of our
> > total observer
> > >moments.
> >
> > Indeed so, I know only too well what you mean. This has
> > come up more
> > than once on the list.
> > I hope you understand why I say it's irrelevant. _Just
> > like_ in the A/B
> > case, it would be wrong to not use Bayesian reasoning just
> > because seeing A
> > is, yes, compatible with both #1 and #2. Seeing A could even
> > have been a
> > way to confirm theory #2, if the rival theory #1 hadn't
> > existed. The bottom
> > line is that Bayesian reasoning usually works for most people.
> >
> > - - - - - - -
> > Jacques Mallah (jackmallah.domain.name.hidden)
> > Physicist / Many Worlder / Devil's Advocate
> > "I know what no one else knows" - 'Runaway Train', Soul Asylum
> > My URL: http://hammer.prohosting.com/~mathmind/
> >
> > _________________________________________________________________
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Received on Mon Sep 03 2001 - 18:52:07 PDT