Defense Intelligence Reference Document The Space Communication Implications Of Quantum Entanglement

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conditions. Thorne and coworkers showed that "nearby" to any inconsistent paradoxical
situation involving timelike wormholes there is always a self-consistent situation that
does not involve a paradox. As Sherlock Holmes said, "When the impossible is
eliminated, whatever remains, however improbable, must be the truth." These
speculations assert that equipment failure producing a consistent sequence of events is
more likely than producing an inconsistency between the send and receive events. The
implications of this are that bilking itself is impossible, but very improbable events
could perhaps be produced in avoiding it.
The other issue raised by retrocausal signaling might be called the "immaculate
conception" paradox. Suppose you are using the setup described above, and you
receive from yourself in the future the manuscript of a best-selling novel with your
name listed as the author. You sell it to a publisher and become rich and famous. And
when the time subsequently comes for transmission, you duly send the manuscript
back to yourself, thereby closing the timelike loop and producing a completely
consistent set of events. But the question is, Just who wrote the novel? Clearly, you did
not; you merely passed it along to yourself. Yet highly structured information (the
novel) has been created out of nothing. And in this case, nature should not object,
because there was no bilking, and you produced no inconsistent timelike loops.
It is not known how to resolve either of these paradoxes. Here are a few possibilities:
• If nonlocal signaling is impossible, then the paradoxes need no resolution, but better,
more "air-tight" proofs of the impossibility of nonlocal signaling would be needed.
• If nonlocal signaling is possible and can be used to form timelike loops, then
paradoxes become important subjects for further experimental testing, study, and
theoretical treatment.
• As suggested by Stephen Hawking (Reference 24), perhaps nature "abhors" timelike
loops, so that if one is about to be created, quantum vacuum fluctuations will grow
without limit and destroy the apparatus that is attempting to produce the loop. Even
in this case, use of nonlocal signaling might still be possible, provided timelike loops
were carefully avoided in such systems. (See below.)
X. Superluminal Communication Without Paradoxes
One path to avoid the retrocausal paradoxes outlined above would be to make sure
there were no timelike loops in the communication system. This can be achieved by
careful arrangement of the propagation delays in the sending and receiving ends of the
hypothetical nonlocal communication.
Consider the space-time interval 5, as defined by the equation: 5 2 = x2 - (ct)2, where
x is the spatial distance separating two events (for example, send and receive), t is
their separation in time, and c is the speed of light. A positive value of 5 2 means the
interval is spacelike and 5=0 is a lightlike interval, and a negative value of 5 2 means
the interval is timelike. The interval s is a Lorentz-invariant quantity that, in particular,
retains its sign independent of the choice of inertial reference frame from which the two
events are viewed.
As long as the nonlocal communication system is arranged so that the space-time
interval between the sender and the receiver is always separated by a spacelike or
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