On Thu, Mar 14, 2019 at 10:50 AM Lawrence Crowell < goldenfieldquaterni...@gmail.com> wrote:
> An entanglement can swap or a bipartite entanglement can enter into an > entanglement with another state. So the entangled state c(|+>_1|->_2 + > |->_1|+>_2) can couple with the system in a superposition c(|←> + |→>) to > become, depending upon the interaction and conservation principles etc to > be > > c(|+>_1|->_2 + |->_1|+>_2) + c(|←> + |→>) → b(|+>_1|←> + |->_1|→>) + d(|->_2 > + |+>_2) > > which would be an entanglement swap. It might however form a tripartite > entanglement > > c(|+>_1|->_2 + |->_1|+>_2) + c(|←> + |→>) → > > b(|+>_1|->_2|←> + |->_1|+>_2|→>) + c(|->_1|+>_2|←> + |+>_1|->_2|→>). > > Here normalization factors can be easily calculated. For the first to > happen there is a Hadamard gate on the two initial states. For the second > there are CNOT type operations that creates an entanglement. CNOT gates > demolish or generate entanglements. > I do not really understand this. Particles 1 and 2 are entangled, say in the singlet state as above. But the particles are well separated, so any interaction with a third particle can affect only one of the two originals. This seems to be what your first possibility shows -- the interaction of one of the entangled pair with a third particle destroys the original entanglement, but might result in the interacting particle becoming entangled with the third particle. Except that your expansion seems to deny the non-separability of the initial entangled state. The second possibility you list seems to deny the non-separability of the initial state right from the start -- only one of the initial particles can interact with the third particle, and that does not entangle the non-interacting partner. Bruce -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
