FTL by Down-converting (DRAFT #4) It may be possible to achieve faster than light (FTL) communication by the use of down-converters. A down-converter splits a photon into two photons each having half the energy of the original photon.
Suppose we have a sender Alice, a receiver Bob, and an intermediary facilitator Charlie. Charlie uses a beam splitter to create two beams of light: L the left beam and R, the right beam. Charlie then down-converts the L beam to create beams L1 and L2, and similarly creates beams R1 and R2 from the beam R. Beams R2 and L2 are normal path or "signal" photons through the down-converter, while beams R1 and L1 are called "idler" photons. By "beam", here, we can mean a flow of individually detectable photons sent in very short intervals so as to provide a useful rate of communication. Charlie directs beams L1 and R1 to Alice and beams R2 and L2 to Bob. The corresponding photons arrive at both Bob and Alice at nearly the same time, but here assume Alice receives hers first. Bob directs beams R2 and L2 such that they can create an interference pattern in a set of detectors. The signal photon beams R2 and L2 can create such an interference pattern because they are the two paths from a beam splitter. Bob will in fact see such an interference pattern provided Alice does not put detectors in idler beams R1 and L1. If Alice does place detectors in both her beams, then this is equivalent to knowing which path each of Bob's photons have traveled, and thus Bob can observe no interference pattern. This known-path-no-interference result has been characteristic of numerous versions of the two slit or two path interference experiments. Now, since Alice and Bob could be light years away from each other, and since Alice thus might have years from the time Charlie released the photons to make the choice to detect or not detect her photons, faster than light communication from Alice to Bob must be a possible result. Assuming that beams adequate for fast communication can be generated and the resulting interference detected sufficiently fast, achieving high data rate FTL communication at short range then primarily boils down to how fast Alice can switch from a detecting mode to a non-detecting mode. This might be as simple as her redirecting beams R1 and/or L1, or by switching on and off the information from her detectors. This experiment then, in addition to achieving FTL communication, may be very useful for determining exactly of what an observation consists. Regards, Horace Heffner
