Re: Recreating people [was: renaissance people]

From: Robert J. Bradbury (bradbury@aeiveos.com)
Date: Mon May 15 2000 - 19:35:52 MDT


Ok, I've done some research and will try to point out some of
the problems with claims being made on this thread.

>From Dan:
> Interestingly, it has recently been demonstrated that we live in an open
> universe consisting of roughly 5% matter, 35% dark matter, and 60% dark
> energy.

I believe this is from a commentary by Joel Primack, based on an article
by Eric Gawiser, Joseph Silk, Science 280: pgs 1397-1411 (several articles).

The Primack quote:
"best agrees with the data is a model in which the universe is made
 of 70% cold dark matter, 20% hot dark matter, and 10% ordinary matter."

Gawiser & Silk:
"The combination of detections of anisotropy in cosmic microwave
 background radiation and observations of the large-scale distribution
 of galaxies probes the primordial density fluctuations of the universe
 on spatial scales varying by three orders of magnitude. These data are
 found to be inconsistent with the predictions of several popular
 cosmological models. Agreement between the data and the cold + hot
 dark matter model, however, suggests that a significant fraction of the
 matter in the universe may consist of massive neutrinos."

(a) If a fraction of the galaxies evolves life early and consumes the
    material, going "dark", the "large-scale distribution of galaxies"
    *and* the cosmic microwave background "fluctuations" may be
    misinterpreted. So *both* data sets on whigh the conclusions
    are base require a dead universe.

(b) I haven't seen any evidence from physics experiments suggesting
    that massive neutrinos (hot dark matter) exist.

The last sentence of this paper:
"If the rapidly improving Type Ia supernovae observations follow current trends
 there may be enough statistical power in the direct observations of cosmological
 parameters to make OCDM and Lambda-CDM preferred to CHDM, although in that case
 none of these models would be a satisfactory fit to both the supernovae and
 structure formation observations."

So even they admit current obervational trends would contradict their
conclusions and *none* of the models seem to be able to reconcile all
of the obervational data. (This article is ~2 years old *and* the
supernova data in published works did continue the observational hints
of that time -- though I've been told by a scientist from JPL that there
are were questions about the SN Type Ia conclusions).

On Mon, 15 May 2000 Spudboy100@aol.com wrote:

> Yes indeed, I am aware of the new discoveries recently in measuring
> background radiation and its rammifications.

I'll simply note that the de Bernadis paper in nature (27 April, 2000, p 955)
says within the 95% confidence interval, omega_0 is 0.88 < 0 < 1.12.
That is not "proof" for a flat universe, only a suggestion.

More importantly, again the last sentences of the paper:
"Our data clearly show the presence of power beyond the peak at l = 197,
 corresponding to smaller-scale structures. The consequences of this fact
 will be fully analysed elsewhere."

I've seen at least one comment that those "smaller scale structures"
conflict with most of the theories.

> There jury isn't out and may not be out for centuries; but yes it does appear
> to be expanding at a faster rate.

Only if the Type Ia SN data holds up. Given the suspicions that are
building that we are missing a proper accounting for the heavy elements
there is no telling how SN Ia brightnesses should vary as they become
more distant (and therefore from "younger" universe eras).

> "Andrew Weil" suggested in his book, The Age of Spiritual Machines,

I think you mean "Ray Kurzweil".

> that whatever the Constants of the Universe are; it won't matter,
> because whenever these constants come up against Intelligence,
> these constants effectively crumble.

Hardly. Kurzweil is a bright guy and a good programmer but that
hardly qualifies him to prognosticate that we (or SIs) can change the
laws of the universe. In fact if you read in detail all of the work
being done on keeping Moores Law going, it becomes clear that
we *are* getting closer and closer to the limits. And as I
point out in my MBrain discussions, the speed of light places
a fundamental limit on who "smart" you can get. Planck sizes
place fundamental limits on how small you can get. Gravity
places fundamental limits on how dense you can get before you
*disappear* from this universe.

Robert



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