On Wed, 12 May 1999, Russell Standish wrote:
> Yes, I know you have explained your position many times, and each time
> I've read such a post from you, I have thought that your argument is
> flawed. Essentially, I suspect that you do not see the difference
> between Bruno Marchal's first person picture, and his third person
> picture.
If the two 'pictures' give conflicting predictions, one of them is
wrong.
In special relativity, for example, is well that many things
depend on what coordinate system you use; but predictions of what a given
observer will observe are invariant. If it was not so, the theory would
make no sense.
> I somwhat dispair that anything I can say could convince you, or vice
> versa, and that we waste a lot of time on unproductive things.
My hope is that Max Tegmark will realize his error and convince
the rest of you. Max, are you there?
> > > Because my
> > > current age is less than the mean human lifetime, I can say that I'm
> > > currently living in a typical time. However (assuming the validity of
> > > QTI, which I do), if I find my self much much older than the mean
> > > human lifetime, then I must be living in an atypical world. This world
> > > may also be one in which homo sapiens far exceeds the usual species
> > > lifetime (assuming there is such a value). It will probably also be
> > > one in which evolution has largely stopped.
> >
> > The above comments appear inscrutable, or less charitably
> > nonsensical, to me.
>
> This again is not a productive way of expressing this. These comments
> follow as simple consequences from the earlier statement. I'm sure a
> Bayesian could express the concept more mathematically, but I don't
> that would improve understanding from your point of view.
Perhaps if you tried to write it mathematically, it would help you
find out for yourself if it is a well defined statement or a bunch of
gibberish.
> > From: Marchal <marchal.domain.name.hidden>
> > To: "Gilles, Jacques, Nick..." <everything-list.domain.name.hidden>
> > >There is no sense in counting worlds in which I do not survive.
> > >Typicality or likelihood are relative to the observer.
> >
> > What about worlds on which others survive? How do you even
> > distinguish between "you" and others to make such a distinction? And of
> > course time should not be a consideration: Measure is NOT conserved over
> > time! There is NOT an equal chance of finding yourself at one age as at
> > an older age! If there was it would disprove the MWI!
>
> Again this depends on what picture you use (ie what filter you use to
> loom at the universe) From the third person picture, you are quite
> correct. From the first person picture, measure is conserved (at 1), except
> in a catastrophic case where at some point in time, the measure
> vanishes
So according to your statement, the predictions of a theory depend
on which 'picture' you use. That is nonsense.
A theory predicts some measure distribution on the space of
conscious observations. From the point of view of an observer, you see
one observation drawn from that measure distribution.
If measure were conserved for a particular individual as a
function of time, you immediately have 2 problems:
- How to define a particular individual? You need to, or else the
measure of other people would count too, and would stay relatively
constant as opposed to the rapidly diminishing measure of "you".
- The expected value of your age would be infinite, contrary to
observations which indicate no unusual age on your part.
From: Higgo James <james.higgo.domain.name.hidden>
>Jacques wrote:
>>Newsflash: If a theory predicts something, and it's found to be
>>true, that's evidence for the theory. If it's found to be false, or that
>>what is observed is atypical of what the theory predicts, that's evidence
>>against the theory.
>
>Newsflash (2): if 2 theories predict the same thing, and it is found to be
>true, that is evidence for neither theory.
Are you saying that the MWI does not predict immortality, or that
a single world theory does predict it? The former would make sense since
immortality is observationally false, but I didn't think you'd come around
so easily.
- - - - - - -
Jacques Mallah (jqm1584.domain.name.hidden)
Graduate Student / Many Worlder / Devil's Advocate
"I know what no one else knows" - 'Runaway Train', Soul Asylum
My URL:
http://pages.nyu.edu/~jqm1584/
Received on Wed May 12 1999 - 15:37:41 PDT