| From: | Adam Getchell acgetchell@*******.edu |
|---|---|
| Subject: | Technological Teleportation/Energy Sources |
| Date: | Tue, 16 Mar 1999 16:58:23 -0800 |
them right now, and Matt Visser's book is close at hand, so:
>The only decent method of bulk teleportation is an Einstein-Rosen Bridge,
An Einstein-Rosen bridge will not work. Crossing one is invariably fatal,
the equivalent of jumping into a black hole.[1]
The Schwarzschild solution to the equations of General Relativity predicts
the "familiar" black hole (which we all now know that the universe may be
one ;-)
The Einstein-Rosen bridge is just a coordinate change to make the
Schwarzschild sigularity "disappear". Modern physics distinguishes between
coordinate singularities (an artifact of your spacetime metric) and
physical singularities. The Einstein-Rosen bridge is just a "coordinate
system (such as, for instance, isotropic coordinates) that only covers the
two asymptotically flat regions of maximally extended Schwarzschild
spacetime." [2]
Just because your coordinate system doesn't cover the singularity doesn't
mean you won't die when you encounter it.
However, I ran a Traveller game that used wormholes that could work. These
are Morris-Thorne wormholes. I think a few Earth masses worth of black hole
would make a gate about 10 meters wide. Unfortunately, they require two
difficult things to make them work (aside from getting together the mass,
making the black hole, cancelling out tidal effects, and making sure
nothing drops in the black hole to incinerate your travelers with
radiation):
1) Negative energy density
2) Exotic matter to prop open the throat to make it traversible by ordinary
people
A negative energy density is almost, but not quite, the equivalent of
negative mass. Unfortunately, no one has ever seen negative mass
(antimatter has positive mass) but there is one way to get negative energy
density: the Casimir effect.
The basics of the Casimir effect is that the vacuum fluctuation energy
(which arises from the sea of elementary particles appearing and
disappearing within the bounds of Heisenberg's Uncertainty Principle set as
the Energy*Time < Planck's constant divided by 2 pi otherwise known as
H-bar) is less near a boundary such as a metal wall. The Casimir force
arises between two metal plates because the energy density of the vacuum
fluctuations is less between the plates than outside the plates.
By the way, this is the basis for several hoaxes about "Free Energy from
the Vacuum" going around. Yes, there's energy there. One can naively do
calculations for how much, but from astrophysics we know that vacuum
fluctuation energy is at least 22 orders of magnitude less than what is
predicted, or else the universe would have hyperinflated so fast that you
could not see your hand. That's another topic.
At any rate, one could use the Casimir effect to generate negative energy
density which must be at 10E-22. Unfortunately, calculations indicate this
requires two concentric metal shells of Earth size separated by an Angstrom
(10E-10 meters) or less. Not real likely.
Exotic matter is stuff like WIMPs from Astrophysics (Weakly Interacting
Massive Particles) or other stuff that has significant mass but doesn't
interact with normal matter. So you use it to hold open the wormhole while
you walk through it.
However, through some complicated 4D gyrations, once you have a
microwormhole, assuming you can keep the thing from exploding, you can grow
it. So in my Traveller campaign I assumed they found one buried in an
asteroid.
The energies involved are immense. To keep a wormhole restrained, you
essentially have to be able to contain the force of an exploding nuclear
weapon. Not to mention the nasty Cosmic Censorship principles involved if
you happen to cross wormhole worldlines.
There's an involved tract on this stuff at my traveller site at
http://hapkido.ucdavis.edu/traveller/, but I'll have to put those pages
back up (currently down) if there's interest.
>The "quantum tunneling" notion of teleportation is only effective across
>very short distances for individual particles. Yes, you can arrange that
>individual particles can "leak" across a solid barrier. The probability
>involved decays exponentially with distance (and we're talking microscopic
>distances here), and coercing an organized batch of particles to suddenly
>tunnel simultaneously and arrive at a new position in their same organization
>is well beyond our current understanding of physics.
Quantum teleportation works. Unfortunately, it requires phase-entangled
particles (photons, etc) which are general made from pair production or
nonlinear optics. No way to apply this to a material body in the forseeable
future.
Another possibility is the Albuquierre space warp. Last time I checked the
literature, though, it had some fundamental flaws, but I don't remember
what they were.
References:
[1] C.W. Misner, K.S. Thorne, and J.A. Wheeler. _Gravitation_. W.H. Freeman
and Company, San Francisco, 1973
[2] Matt Visser. _Lorentzian Wormholes, from Einstein to Hawking_. American
Institute of Physics, Woodbury, 1996
--Adam
acgetchell@*******.edu
"Invincibility is in oneself, vulnerability in the opponent." --Sun Tzu
