Re: The Next Century's Great Discovery

Hal Finney (
Mon, 28 Jul 1997 15:01:04 -0700

Eric Watt Forste, <>, writes:
> (There's also a neat little chart on the web, pointed out here
> recently by Steve Witham, at
> that makes things a bit more concrete. "The figure below illustrates
> how little one needs to change some aspects of our world to make
> it hostile to life...")

I missed the earlier reference, but this was a neat web page. I liked
the chart showing the relationship between different mathematical objects.
It would be great as a large-format wall chart. This guy, "Mad Max" Tegmark,
has some pretty cool physics stuff on his home page, too.

One problem I have with Anthropic Principle reasoning is the claim
that atoms and molecules much as we know them are necessary for life.
I don't see how we can a priori rule out possible stable structures of
others kinds. Even in our own universe, it could be that an earlier or
later epoch would allow the existence of life in a totally different way.
We, who seriously consider the Moravec/Tipler picture of transforming
ourselves into standing waves during the collapse of the universe,
cannot be too confident that life depends on atoms.

Even if we do grant that atoms are necessary, there is inevitably going to
be some "slop" in the physical constants which will allow life-supporting
universes. Maybe they will have to fall into a narrow range, but there
will be *some* variability possible. So all the AP can really do is to
reduce the magnitude of the problem. The essential mystery will remain:
are there infinite universes, most of which have no life? Is there just
one, and somehow it was created in the preferred state where life can
evolve? I think there is a substantial issue here even accepting the AP.


P.S. Here is an abstract from another of Tegmark's papers on his site:

"At first sight, an accurate description of the state of the universe
appears to require a mind-bogglingly large and perhaps even infinite
amount of information, even if we restrict our attention to a small
subsystem such as a rabbit. In this paper, it is suggested that most
of this information is merely apparent, as seen from our subjective
viewpoints, and that the algorithmic information content of the universe
as a whole is close to zero. It is argued that if the Schrödinger
equation is universally valid, then decoherence together with the
standard chaotic behavior of certain non-linear systems will make the
universe appear extremely complex to any self-aware subsets that happen
to inhabit it now, even if it was in a quite simple state shortly after
the big bang. For instance, gravitational instability would amplify the
microscopic primordial density fluctuations that are required by the
Heisenberg uncertainty principle into quite macroscopic inhomogeneities,
forcing the current wavefunction of the universe to contain such Byzantine
superpositions as our planet being in many macroscopically different
places at once. Since decoherence bars us from experiencing more than
one macroscopic reality, we would see seemingly complex constellations of
stars etc, even if the initial wavefunction of the universe was perfectly
homogeneous and isotropic."