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Entanglement Swapping Superluminal Communication

  1. Mar 7, 2014 #1
    I'm wondering whether or why quantum entanglement swapping or steering could or couldn't be used for superluminal communication. Below is a thought experiment. Setting aside the technological barriers do the laws of physics prevent this?

    On Earth Base Alpha:

    EPR Sources Entangle Numbered Particle Categories into Particle Pairs:

    1 & 2 (first)
    3 & 4 (then)
    2 & 3 (then, finally)

    Before particle 3 & 4 entanglement, sensors measure the quantum state of particle 1 and thus determine the anti-correlated quantum states of both particles 1 & 2.

    Particle 1 is destroyed or discarded, category 2 particles are grouped into 2 separate containers by their already determined quantum state (e.g., 2A, 2B; where A: up spin, B: down spin, etc.).

    Next, particles 3 & 4 entangle.

    Then, particles 3 & 4 are sorted into their respective containers and “captured in sequence” in the same order each particle is entangled & received.

    Alpha Base: retains the containers of particles: 2 & 3.

    A rocket ship transports the particle 4 container to Moon Base Beta.

    Alpha Base sensors begin taking “projection measurements” of particles 2 & 3, thus entangling them.

    Beta Base sensors take slightly delayed measurements of the individual 4 particles which are the companions to 3 particles (which were just entangled with 2 particles).

    With this process, Alpha Base can “steer” the quantum state of category 4 particles.

    That is, by entangling particle 3 with 2A particle, particle 4 spins down; or spins up for particle 3 & 2B entanglements. Because of the slight delay, particle 4 measurements alerts Beta Base to Alpha Base’s steered quantum state choice.

    Therefore, by modulating particle 3 & 2A and 3 & 2B entanglements, Alpha Base transmits and Beta Base receives superluminal Morse code.

    Does this violate relativity?
  2. jcsd
  3. Mar 7, 2014 #2


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    See http://curious.astro.cornell.edu/question.php?number=612 [Broken]
    and the referenced articles.
    Last edited by a moderator: May 6, 2017
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