Of course it does, and everyone here is agreeing with you about that. That's not the issue.WHETHER ENTANGLEMENT SWAPPING OCCURS STRICTLY DEPENDS ON VICTORS MEASUREMENT.
Exactly the example I gave earlier, where determining whether entangle swapping occurred or not was not possible without knowing from Victor what measurement he performed (which requires a classical channel).So I have to repeat the question I asked a few posts back: can you tell me, in detail, precisely how Alice and Bob, given just their measurements of photons one and four, can determine whether they have been entanglement-swapped? I assert that that it is not possible ....
Yes - I think we also all agree that it's possible if we have access to Victor's records as well, and enough samples to detect the correlations with statistical significance. Indeed, that's the point of the paper that seems to have so misled matrixrising. The impossible challenge is to determine whether swapping has occurred just on the basis of Alice's and Bob's measurements.Exactly the example I gave earlier, where determining whether entangle swapping occurred or not was not possible without knowing from Victor what measurement he performed (which requires a classical channel).
I have no idea what the above represents. What's +23 or -23? Alice has 1 bit (H or V), and Bob has another bit. Those form pairs of bits. I asked what those pairs would look like, and made it clear how to answer. Please address this, and write it in the form per below so you can see the true situation:Edit: It would look like this:
HH23HH23VV23HH23VV23VV23 = 0 ( a separable state)
+23+23-23-23-23+23+23-23+23-23=1 (a Bell state)
I'm sorry, I may not have been completely clear about what my question is. I'll try again.Alice and Bob have the data about the entanglement of 1&2 and 3&4 that's being swapped.
Entanglement swapping leaves a distinct signature that can be used to encode information ...
BINGO!I'm sorry, I may not have been completely clear about what my question is. I'll try again.
What exactly is this "distinct signature"? How do Alice and Bob recognize it when they see it?
Or, to be even more specific: Alice measures photon one and gets a result, either up or down, on some measurement axis. Bob measures photon four and gets a result, either up or down, on some measurement axis. How do they use the two measurement results to determine whether Victor has chosen to do an entanglement swap? Do they need any other information than those two measurements, and if so, what is it?
What exactly do you mean by "the data from the entanglement that's being swapped"? Again, be precise - how is it measured, by whom, when?THE DATA FROM THE ENTANGLEMENT THAT'S BEING SWAPPED!
Victor, Bob and Alice know the data on the entanglement of photons 1&2 and 3&4. Bob and Alice use this data to know whether entanglement swapping has occurred. If all 3 bases show strong quantum correlation between photons 1&4 then they know entanglement swapping has occurred if not then they know it hasn't occurred.