[extropy-chat] What if Dyson spheres are obsolete? (was the Drake Equation)
avantguardian2020 at yahoo.com
Fri Oct 27 19:51:37 UTC 2006
--- Anders Sandberg <asa at nada.kth.se> wrote:
> The Avantguardian wrote:
> > One of the "possibilities" that I think you guys
> > to be missing is that it may turn out that
> > dark/vacuum/zero-point energy may actually be
> > than building a Dyson sphere.
> To join with the choir, why do you think this? I
> could make the claim that
> breaking the law of conservation of angular momentum
> is even easier than
> building an electric motor - but without any idea of
> how to do it the
> claim just becomes an unsupported claim.
I think you are missing my point. I wasn't necessarily
making a positive claim about vacuum energy so much as
offering the negative claim that the reason that the
universe is not over-run with Dyson Shells blotting
out the stars is that such technology is less
practical then something else.
What that something else is, I don't know. I threw
vacuum energy out there because at least it is
something that is *observed* if not well-understood.
Vacuum energy may be a total bust, but that doesn't
mean that there isn't something better than Dyson-tech
waiting to be discovered. You guys remind me of 18th
century scientists plotting to use steam engines to
take over the world, not realizing that internal
combustion would be right around the corner.
> Vaccum and zero-point energy appears to be highly
> entropic and/or
> isotropic and you need a difference to set up a
> thermodynamic engine. It
> is unlikely you could get any energy from suffling
> them around within
> their own domains. If ZPE or dark energy are to be
> regarded as istropic
> heat reservoirs with a different temperature than
> the reservoir of the
> visible universe then one could get energy by having
> a heat flow between
While I wasn't actually intending to get into a nuts
and bolts discussion about potential ways to utilize
ZPE, since you brought it up and it is an interesting
subject to me, I will humor you.
I agree that the biggest problem with vacuum energy is
its isotropy or as I like to think about it, symmetry.
While this is obviously the default in free-space,
there could very well be a way to break this symmetry
and generate an isotropy.
One way that is pretty well established is Hawking
radiation. If you can throw half your vacuum
fluctuation into a black hole, you could theoretically
use the other half to scoot around the galaxy.
Unfortunately this is not very practical as we can't
carry black holes around in our pockets and there are
no known ways of generating an artificial event
horizon. (Except for relativistic speeds but if we had
that, we wouldn't need vacuum energy)
> But if this was easily possible it would have
> happened a long time
> ago, likely during the big bang. There might still
> be some clever way of
> doing it that doesn't naturally occur, but I haven't
> seen any convincing
> idea of how to do it.
Well I dare say it won't be easy. Life seldom is. They
have been doing a lot research on the casimir effect
lately and there are some interesting developments.
For one thing they have found that the vector of the
force seems to be highly dependent on geometry. Some
geometries leading to attractive forces and some
geometries leading to repulsive forces. Perhaps their
is some magic geometry that will allow the generation
of an asymmetric force.
Another possiblity I have been thinking about is to
use phase cancellation on the vacuum energy. Kind of
like when you hook up one of your speakers backwards
and don't hear anything because the peaks of sound
from one speaker correspond with the valleys from the
other speaker. If you could emit 180 degree
phase-shifted EM waves from your front side, the
normally phased vacuum fluctuations behind you should
theoretically be able to push you around.
How you would generate the right mix of phase-shifted
frequencies to do this, however, I don't know.
> One of the funnier approaches I've seen was to use
> Casimir forces to
> extract energy from two horisontal plates by having
> them move together
> vertically, then slide them apart horisontally,
> returning them to the
> original position. Alas, a careful analysis (I have
> the paper *somewhere*)
> show that there is Casimir forces resiting the
> return to the original
> state in such a way as to make the energy gain zero.
While it is MUCH easier to perform calculations of the
casimir force on flat plates, it is probably the
geometry that is least likely to yield useful work for
> I'm open for the possibility that there is some
> magical physics out there,
> because I think the universe looks even M-brain
*Some* magical physics? All physics is magic . . .
just ask the aborigines or the nematodes. ;)
> There ought to be a
> few von Neumanns out there anyway, and we are not
> seeing anything. My
> guess is that there is some physics that once
> discovered leads to a very
> discreet civilization.
Or perhaps a very lazy one. Even as we speak, there
may be intelligent beings out there debating our
existence momentarily before going back to playing
> Hopefully it is of the baby
> universe or moving down
> to the Planck scale kind, and not of the kind that
> any sufficiently
> advanced civilization can wipe out any other civ it
> knows about instantly
> anywhere and hence keep very, very quiet.
That is a possibility. But it would actually only be a
possibility if there were MORE than one other
civilization out there and they already knew about at
least one other civilization each.
To destroy a civilization, no matter how easy it is,
would be a waste of time unless that civilization had
something you wanted (like land to colonize).
For what it is worth, there are probably very few
technological civilizations out there. While the
universe is certainly not sterile and there are
probablly billions of planets with life, if Gould was
right, increasing complexity is not the vector of
evolution, just a happy tangent.
But then again . . . who says Gould was right? :)
alt email: stuart"AT"ucla.edu
"Believe nothing. No matter where you read it, or who said it, even if I have said it, unless it agrees with your own reason and your own common sense."- Siddhartha Guatama aka Buddha.
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
More information about the extropy-chat