Re: Infinite universe

From: Gary F. York (
Date: Mon Apr 28 2003 - 17:54:49 MDT

From: "Perry E. Metzger" <>

> "Ben Goertzel" <> writes:
> > I can see that this Library of Babel metaverse is possible, but I'm not sure
> > why it's necessary...
> It is all around you by definition. We have:
> 1) A physics in which any given volume can only hold a finite number
> of possible states.
> 2) A physics that, thanks to quantum mechanics, generates nice even
> distributions of states.
> 3) Initial conditions that apparently consisted of (from the WMAP
> data) mostly uniform distribution of matter and a flat and thus
> infinite space filled with that matter.
> That means if you only go far enough, you'll eventually find a volume
> with any given configuration. This assumes that the universe is as the
> cosmologists currently believe it to be -- which might change with
> time, of course.
> --
> Perry E. Metzger

I'm unpersuaded for reasons I'll get to in a moment. I should confess that I
most particularly don't _want_ to be persuaded. Seems to me the implication is
utterly horrible: every evil, monstrous act that could conceivably be
perpetrated must have happened -- somewhere. For this to be true, every exact
doppelganger of me which exists at this time, N, there must be an infinite
number who 'choose' to do some completely irrational, horrible thing at time N +

I don't think this is actually possible. If we consider the movement from time
N to N + 1 as a state change, my contention is that some state changes are
constrained. Any arrangement of atoms and molecules configured at time N as
_me_ is not, for instance, going to move at N + 1 to a state that cuts open the
next baby it sees to see if it likes the taste of baby heart. It's not just a
low probability event, it's a zero probability event.

The whole point of designing a 'friendly' AI is based on the presumption that
it's possible to succeed -- which means that the AI, designed properly in the
first instance, has zero chance of becoming unfriendly. At a lower level, if I
create a program to print out the integers, there are some ways I could err, but
it has zero chance of printing the works of Shakespeare instead.

Perhaps this is obvious.

The point is that estimating the maximum distance to my nearest doppelganger by
first computing the number of Hubble bubble's it would take to instantiate every
possible state within a Hubble bubble places an upper bound on the distance but
is very far from establishing that every imaginable configuration of states is a
_reachable_ state in state space under the state transition rules that represent
the laws of physics.

That I exist is an instance proof that there is at least one set of state
transitions that could lead from conditions at the beginning to me. So,
granting the assumptions, there may in fact be doppelgangers of me out there and
very likely much closer than the estimate given. (Because the number of
_reachable_ states in state space is very much less than the number of
imaginable states.)

But -- maybe not, either. The simplifying assumption leading to the
doppelganger hypothesis was nearly uniform mass distribution and infinite space
containing, logically, an infinite number of Hubble Bubbles with _exactly_
identical initial particle distributions. The presumption seems to be that
given identical mass distributions, events would proceed, deterministically, in
identical ways, thus leading to doppelgangers for those volumes with initial
distributions (and temperatures) equal to our own.

There is at least one unstated assumption: that position, relative to the center
of the inflation, has no influence on subsequent events and that, therefore,
it's reasonable to expect particle interaction to proceed identically in
different 'equivalent' bubbles. This might be true. But it might not be true,

I certainly don't have the math or physics to understand the inflationary
universe idea with any depth. Still, it seems that if we stipulate inflation,
there is _some_ equivalent of motion and, if so, every particle might have it's
own unique starting vector so that even if 'initial conditions' were
positionally equivalent for two distinct volumes at some early time T, then
those two volumes would be positionally _much_ different at time T + 1.

Even if I'm utterly wet in this instance, surely one among you can propose
something plausible that leads neither to horror nor unimaginably tedious


Gary F. York

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