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Hal's Extropians Digest      Tue, 23 Jun 1992       Volume 92 : Issue   0013

    Selected messages from the Extropians list.  To join, send to:
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    Hal Finney
    Extropians Digest Moderator

Today's Topics:
			  costs of insurance
		      Nuclear power versus solar
		   Bell's Theorem and Alain Aspect
		      Biosphere II (2 messages)

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Date: Tue, 23 Jun 92 13:29:09 EDT
From: uunet!shearson.com!pmetzger (Perry E. Metzger)
To: Extropians@gnu.ai.mit.edu
Subject: costs of insurance

In Re: cryoprocrastination

Having been exploring life insurance recently, it appears that there
really is no excuse for the young, and healthy but poor not to get
signed up with Alcor. $50k in term life from SBLI will cost a 24 year
old non-smoking male about $65 a year! Admittedly term isn't the best
way to go for good, but if you are a poor grad student it gives you a
more than adequite interim measure. The annual cost of the emergency
responsibility fee plus term insurance is completely within reach of
even fairly poor individuals!

Given all this, isn't it about time you signed up...

Perry

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Date: Fri, 19 Jun 92 14:05:17 CDT
From: uunet!hsvaic.boeing.com!eder (Dani Eder)
To: Extropians@gnu.ai.mit.edu
Subject: Re: New clear power (was Re: The Environment)

Advanced photovoltaics have a power output on the Earth's surface
of about 100KW-h/m^2/yr.  This is a total energy of 360MJ.  With
a mass of 30kg/m^2, we require 500MJ to make the equipment from
raw materials using efficienct processes.  This is a payback time
in energy terms of 1.5 years.  A nuclear reactor produces 500MW,
and masses, for the containment shell, 50,000 tons.  The production
energy for the entire plant (say twice the mass of the containment,
might be 1.5x10^15 joules, Which implies an energy payback time
of 0.1 years.  Yup, looks like nuclear is more efficient.

Dani

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Date: 20 Jun 92 23:08:42 EDT
From: Michael Clive Price <uunet!CompuServe.COM!100034.3077>
To: Extropians@gnu.ai.mit.edu
Subject: Bell's Theorem and Alain Aspect

Sean has requested a short resume of Bell's theorem.  Sorry, it's
not that short, but I hope it's of some use.

What Bell did was to see how the spin of individual particles,
created in some collision where the total spin was known, are
related to eachother.  With spin the experimenter is free to
choose which orientation of spin to measure along (eg z-axis can
yield spin "up" or "down") and these different orientations are
related to eachother.

For example if two particles, A and B, are created with sum zero
spin and I measure the spin of A as "up" then, by conservation
of spin, I can infer that particle B would yield a spin of "down"
*IF* I measured B's spin along the z-axis.  Life gets more
complicated if I measure A's spin along, say, the x-axis and B's
along the z-axis, but the operational structure of QM still
yields clear predictions for the correlations of spins of A and
B measured along differing axes.  QM also denies that the
particles can possess definite values for any spin components
before you measure it, so the particles have to signal to
eachother via this "spooky" action-at-a-distance wavefunction
collapse mechanism.

Bell looked at these spin correlation predictions and cast them
in the form of inequalities.  These inequalities relate the
proportions of particles that will have various spins.

Bell then took the case where the particles *did* possess
definite spin values at the moment of creation, but were hidden
from the experimenter until measured.  Bell was saying, suppose
that we have a local hidden variables theory.  He came up with
a different, looser, set of inequalities that any such local
theory would impose.  These are the inequalities known as the
Bell inequalities.  The correlations predicted by any local
hidden variables theory are weaker than the inequalities
predicted by conventional QM.

Experiments were done in the 1970s and the results, Bell's
inequalities being breached, seemed to rule out local hidden
variables - that is to say that conventional QM was upheld with
its apparent action-at-a-distance FTL signalling effects that
Einstein and others so objected to.

But this was not the end of the story.  Some people objected.
To rule out the non-local hiddem variables you should really
ensure that your measurements on the particles should be timed
so that they occur outside eachothers' light cones - i.e. if
you're measuring their spins when they are separated by a few
metres then this should be done over a few nanoseconds.  Then,
for them to correlate spins in accord with QM, they have to
signal to eachother via some FTL mechanism.

So these experiments were done, by Alain Aspect in 1982 on
polarised photons, the measurements being made as coincident as
possible.  Again local hidden variables seems to be excluded.
FTL signalling seems to be implied.

Some die-hards still objected.  Suppose, they said, that the
particles involved somehow "knew" which spin orientations you,
the experimenter, were going to measure.  Then they could signal
to eachother via some slower than light effect before you
measured their spins.  So more experiments were done, (I believe
by Alain Aspect again, although I'm not sure), with the choice
of spin orientation being selected at the last possible moment
and the measurements being made as coincident as possible.  Again
local hidden variables seem to be excluded.

I guess you could still argue that the spin measurement selection
mechanism was signalling to the photons via some unknown STL
mechanism, but it is getting increasingly difficult for
proponents of local hidden variables to support this position.

The position that most physicists take from these experiments is
that local hidden variables are ruled out and that the apparent
FTL effects of QM are here to stay.  Only three coherent
positions seem left:

1)   non-local hidden variables.  Advocates of this (David Bohm
     with his quantum potential etc) believe that there is some
     FTL effect and devise increasingly arcane experiments
     trying to expose this.  So far they have not been
     successful.  I think Penrose is in this group, insofar as
     he is coherent :-)
2)   complete agnosticism.  Advocates of this throw up their
     hands in horror at our ignorance of the workings of the
     universe and wait for something to emerge from quantum
     gravity / superstrings etc to explain it all.
3)   many-worlds.  Advocates of this accept that physics offers
     a complete description of reality, except in situations
     where quantum gravitional effects dominate (Big Bang, small
     black holes etc).  They believe that any advances to be
     made in this quarter will have no philosophical impact on
     the models physicists use other situations.

I adopt stance #3.  I don't see how quantum gravity is going
change the explanation of way electrons are splattered across my
video monitor or the passage of a photon through a pair of slits
produces an interference pattern.  The apparent FTL effects of
QM result from our inability to view the universe as a whole.
Just as the operation of a powerful searchlight sweeping across
the moon would look like an FLT effect until we spotted the
searchlight so the collapse of the wavefunction seems FTL and
spooky until we realise that it's just a subjective effect of our
necessarily limited vision.  We are being continually copied by
the operation of QM, but each copy is only aware of the world it
finds itself in.

Mike Price

BTW I like the idea of John Gribbin's Doomsday Machine.  I think
the idea of wiring yourself up to an H-bomb to test many-worlds
originates with Sir Fred Hoyle.  Anyone got a reference?

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Date: Fri, 19 Jun 1992 12:53 MST
From: "James J. Lippard" <uunet!CCIT.ARIZONA.EDU!LIPPARD>
To: Extropians@gnu.ai.mit.edu
Subject: Re: Biosphere II


>>(jjl) It's pretty much a mess.  Biosphere II isn't a good point in an
>>(jjl) argument for private scientific research.

>(rjc)   Oh, I don't know about that. The point could be made that
>(rjc) when they screw up, atleast they aren't wasting anyone elses
>(rjc) money but their own.

>(rjc)   How could anyone be against private scientific research? If it
>(rjc) isn't subsidized by your money, and it doesn't hurt you in any way,
>(rjc) why should you care?

That's a reasonable argument that Biosphere II shouldn't count *against*
private scientific research, but it's not much of an argument in favor
of private scientific research.  Scientific research has the goal of
discovering truths (with luck, useful ones).  That goal is not
exemplified by Biosphere II, where the only truths beings discovered
are ways in which a cult-like group can mismanage a scientific project.

I don't think we have much, if any, disagreement here.  I was not making
an argument against private research.

Jim Lippard            Lippard@CCIT.ARIZONA.EDU
Dept. of Philosophy    Lippard@ARIZVMS.BITNET
University of Arizona
Tucson, AZ 85721



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Date: Fri, 19 Jun 92 18:27:42 EDT
From: uunet!ksr.com!chrism (Chris Moriondo)
To: Extropians@gnu.ai.mit.edu
Subject: Re: Biosphere II

> That's a reasonable argument that Biosphere II shouldn't count *against*
> private scientific research, but it's not much of an argument in favor
> of private scientific research.  Scientific research has the goal of
> discovering truths (with luck, useful ones).  That goal is not
> exemplified by Biosphere II, where the only truths beings discovered
> are ways in which a cult-like group can mismanage a scientific project.

Actually, all that this says to me is that you should be very skeptical of
*ideologically-motivated* research.  Even before these latest "revelations", I
viewed Biosphere II as being somewhere between a publicity-stunt and creationist
"research" debunking evolution.  Now we find out that they were willing to lie
to be able to "demonstrate" their argument that a completely sustainable
livestyle is feasable.  This should come as no surprise, at least one of the
major proponents of global warming has argued that it's okay to emphasize the
results that support your point and completely ignore the ones that don't, when
you have an ideological point to make.

As for arguments for or against private research, there is certainly no shortage
of arguments against *government* funded research!  And in a recent article in
Time magazine which argued for greater government funding of research and
development, they started off with a list of great R&D achievements.  The
majority of the items on the list (such as the transistor, the laser, the
integrated circuit, and the discovery of the 3 degree remnant of the big bang)
were the product of privately funded work!  (Admittedly, they didn't seem to
make much distinction between science and technology.)

-chrism

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End of Hal's Extropians Digest Volume 92 Issue #0013
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