[ExI] Many Worlds (was: A Simulation Argument)

[Vladimir Nesov]

On Jan 18, 2008 4:40 AM, Lee Corbin <lcorbin at rawbw.com> wrote:
> Vladimir writes
>
> > Before the toss, you don't know the outcome, so chance is 50%. After
> > the toss, you know the outcome, so chance is either 0% or 100%,
> > depending on it.
>
> What's wrong with that, in my opinion, is that it leads to the fallacious
> deduction that "something didn't happen to me". The truth is that it
> *did* happen to you, it's just that the place where you are forming
> memories of it having happened are in the other branch.
>
> True, we are not accustomed to this, to put it mildly.  Heretofore
> in human history to be experiencing something is to be making
> memories of it;  but now, (either with physical duplicates or
> with the multiverse), something may be happening to you at
> one place without you (at another place) having a clue.

It's not at all fallacious: you changed the definition of 'me'. I'm
talking about probabilities you can use in decision-making. You can
redefine these terms, but what you really are interested in is
decisions you can arrive at in your *current* self, one you control.

After all, all these platonic worlds are only real for you as models
of them that you build yourself (in your head). You can't interact
with real thing, it is not in your world. You can play with a model,
but it's all it is: another mathematical toy.


> > Elements of these common substructures interact (and these
> > interactions are equivalent to being cross-world interactions).
> >
> > But likewise elements that are able to interact is a definition of
> > world. But definition of world needs an 'anchor' substructure, so that
> > it will include those elements that can interact with it. If in above
> > example one of common substructures is regarded as an anchor, it will
> > select different, but intersecting, collection of elements as its
> > world.
>
> Well, I don't know.  That brings up a good question.  Suppose that
> we have a certain granite monument, and we set up bifurcating
> experiment near it, so that after an "up/down" outcome of the
> apparatus, we start to speak about our other selves in the other
> world.  Yet the monument could be---if you are right---judged
> to be a "point of contact".  Just what does that mean experimentally?
> Does it mean that the two branches "share" the monument? Is this
> how we should speak?   Well, why not?  After all, the contents of
> the monument have not diverged (assuming that the radiating
> influences---gravitational for instance---of the experiment haven't
> caused differences).

Yes, it's how I see it. In your world, there is a split, with two
different versions of you observed different outcomes of experiment.
In rock's world, there is no spit, because rock doesn't know about
experiment.

Selection of worlds is a dodgy business. How do you know that world
you live in isn't replaced by another similar world? You don't, you
only know that things that you know about the world don't change. So,
all worlds that contain you having the same knowledge are equivalent
in claiming to be the world you live in. Each 'anchor' subsystem
allows certain set of worlds to contain it, there is a correspondence
between anchor and 'worldset' that contains it.

So, rock's worldset contain worlds with both outcomes of experiment,
and both versions of you. Your worldset, on the other hand, can't
contain both outcomes, because each version of you doesn't allow
incorrect outcome in its world.


-- 
Vladimir Nesov                            mailto:robotact at gmail.com