Can you summarize this article? Please answer in full sentences.

"Mitchell Porter (<PRESIDIO_ANONYMIZED_EMAIL_ADDRESS>)
Tue, 25 Feb 1997 12:09:50 +1000 (EST)
This is one version of what some of us are calling the Linde
scenario. It is predicated upon the possibility of traversible
wormholes and baby universes. Most of what follows is science
fiction rather than technological extrapolation, in the sense
that there's no rigorous argument that the step in question is
possible, but one has to start somewhere.
An updated version of this scenario will live at
http://www.thehub.com.au/~mitch/extro/infinite/linde.html
-mitch
"Wormholes are lunatic fringe technology" - Eugene Leitl
The Linde scenario, v0.01
The basic steps are:
1. Establish an industrial base in space
2. Manufacture wormholes
3. Spawn a baby universe and enter it
4. Tame that universe, spawn more from within it; repeat ad infinitum
In more detail:
1. Establish an industrial base in space.
I assume that this will be necessary for wormhole manufacture, which
may require very low gravity and/or very high energies that are
not available on Earth. Paths to industrializing space have been
described in many places, for example in Marshall Savage's book
_The Millennial Project_ (see http://www.millennial.org).
Essentially this is a matter of locating space resources, reaching
them, and using them.
2. Manufacture wormholes
Here we jump straight into the science-fiction part. I am not aware
of a single reliable scheme for wormhole manufacture. One could
classify schemes as follows:
* Find naturally occurring macroscopic wormholes (e.g. cosmological
remnants)
* Find naturally occurring microscopic wormholes (e.g. from
Planck-scale space-time fluctuations) and inflate them
* Artificially induce a topology change
The first scheme may require travel across light-years, if such
remnant wormholes exist at all; while the second may be problematic
(it would seem to require the creation of an inflationary domain
around the wormhole, and how would you get hold of it again having
done that?).
The third scheme, although in some ways the most speculative, strikes
me as the most promising. String theory has already been used to
describe a form of topology change [Greene, Morrison, Strominger,
"Black Hole Condensation and the Unification of String Vacua",
hep-th/9504145], so perhaps we can imagine that in the 21st century,
when the theory of quantum gravity is mature, we will be able to
figure out how to induce such changes.
John Cramer once suggested (Analog, "The Alternate View", March 1996;
http://www.npl.washington.edu/AV/altvw77.html) that one could make a
mini black hole with an asteroidal mass of rubidium, using Bose-Einstein
condensation, but according to John Baez (in correspondence) Fermi
interactions among nucleons would interfere with this process.
Nonetheless the general idea of making mini black holes using BECs
might work for some other substrate. Perhaps we can then imagine
colliding mini black holes and looking for stable micro wormholes
amongst the collision remnants. (This may sound a little arbitrary,
but I recall reading that the weak energy condition which would be
violated in the wormhole interior is also violated near the
event horizon of black holes. The search for a citation for this
is in progress!)
What would these wormholes be like? Let's assume that they're
spherical wormholes, whose throats are stabilized by exotic matter.
A single wormhole will look like two small balls of exotic matter,
but the inside of one ball is the outside of the other; in other
words, if you could drill into one ball, you would find your drill
emerging from the other. The region of exotic matter would therefore
have the topology of a thick-shelled hollow sphere (S^2 x I).
Having produced micro wormholes, one will want to catch them, store
them, and eventually manipulate them - move the ends around, make
them bigger, make them traversible. All of this depends on the
interactions of exotic matter with ordinary matter; if it has
electric charge or color (chromodynamic) charge, one may be able
to drag it around electromagnetically, store it in nucleonic cages,
and so on.
To make a spherical micro wormhole such as I've described
traversible, it needs to be increased in size at least to nanometer
dimensions, and the shape of the exotic region needs to be changed
so that particles can get through. One might be able to make the
wormhole bigger by manufacturing exotic matter and dropping it in,
or by exciting the exotic matter that already holds the throat open.
As for a traversible wormhole, a donut shape (topology T^2 x I)
might be a simple start. One could try to reach this by causing
the spherical exotic droplet to spin, becoming oblate, and then
by making a pole-to-pole hole in pancake-shaped droplet.
So, the highly speculative procedure described thus far amounts to
* Make micro black holes
* Collide them and look for stable micro wormholes among the products
* Collect micro wormholes and store them
* Introduce energy to make the wormholes bigger, traversible, etc
* Ship them where needed (e.g. to the stars!)
The advantage of microscopic wormholes is that they can probably be
made to move very fast. Nature manages to produce 10^20 eV cosmic rays
[John Walker], which will cross millions of light-years in 30 minutes
"subjective time"; if one could send one end of a micro wormhole into
space at such speeds, within 30 minutes one's home system would have
a wormhole connection to regions of space millions of light-years
away. One might circumnavigate a closed universe in days. This would
lead to the "wormhole empires" described by Michael Price
[Michael Price, "Traversable Wormholes", Extropy #11;
http://www.aleph.se/Trans/Tech/Space-Time/wormholes.html].
Far-travelling wormholes also move far into the future, relative to
the cosmological reference frame (in which the cosmic background
radiation is at equilibrium), so this would be a way for people in
the present to probe the far future of the universe. If our
universe is spatially closed (e.g. with topology S^3), the probing
of the future would be limited by the radius of the universe.
If one's wormhole network expands spherically, one can't send a probe
far beyond the "cosmic antipodes" (the point in space opposite the
network's point of origin) without risking the creation of
closed timelike curves and the likely destruction of one's wormhole
through the Visser effect (or some other chronology protection
mechanism).
Another spin-off of wormhole technology might be unusual rocket
designs, in which reaction mass was fed into the rocket via a
wormhole mounted in front of the engine, from remote stockpiles
of fuel.
3. Spawn a baby universe and enter it
An intriguing recent idea is that, rather than simply collapsing
into a singularity, the region of space constituting a black hole
pinches off from its parent spacetime and (upon reaching sufficient
density) inflates into a new universe. The idea behind step #3
of our plan is to shoot one end of a wormhole into a collapsing
supermassive object, in the hope that it will enter the future
inflationary region, avoid destruction, and survive into the
post-primeval era of the new universe.
I have already speculated that one might be able to make micro
black holes; I might further speculate that they are not very
suitable for the above procedure, because of their smallness
and their brief lifespans. In that case, perhaps we need to
proceed as follows:
* Travel to a star on the edge of supernova
* Introduce very large numbers of caged pico wormholes into
the star (when I say "caged wormhole" I imagine an atomic
nucleus inside which is one end of a wormhole)
* Position them so they will survive stellar implosion,
inflation, and scattering in the new universe
* Wait for collapse...
If everything works, you now have a wormhole link to a second
universe.
4. Tame that universe, spawn more from within it; repeat ad infinitum
Presumably you don't want to wait millions or billions of years for
your new universe to cool, for stars to form, etc. So you open
your transuniversal wormholes (i.e. make them traversible), ship
materials through, build relativistic rockets, cage your wormholes
and put them inside, and then rocket the wormholes into the age
of stellar and planetary formation in short subjective time,
thanks to time dilation.
Now, if you want this whole universe under your control, you
should construct and send wormhole-bearing probes into every
solar system. In supergiant systems, you can repeat steps #3 and #4.
Otherwise, you have a whole new universe in which to construct
megastructures, evolve ecosystems, explore spontaneously-occurring
natural phenomena like natively evolving civilizations, and so on.
-mitch
http://www.thehub.com.au/~mitch
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