Does anyone who understands quantum networking better than I do have an opinion on the testing methodology that the Chinese team used to confirm entanglement? I guess, more specifically, my question is: when they say that they got 911 positive results out of “millions” of attempts, does this significantly exceed any expected false-positive rate for the confirmation methodology? If so, by what margin? Obviously, if you were just flipping coins, and measured the results once, you’d get 50% positive correlation, twice and you’d get 25% correlation, ten times and you’d get 0.1% correlation, and you’d be at 911 out of a million. So, how much better than that are we talking about?

-Bill

Does anyone who understands quantum networking better than I do have an

opinion on the testing methodology that the Chinese team used to confirm

entanglement?

Their paper

https://arxiv.org/abs/1707.01339

This is somewhat higher level

http://vcq.quantum.at/fileadmin/Publications/Entanglement-based%20quantum%20communication%20over%20144km.pdf

More math

https://arxiv.org/pdf/1410.1319.pdf

I guess, more specifically, my question is: when they say that they got

911 positive results out of “millions” of attempts, does this significantly

exceed any expected false-positive rate for the confirmation methodology?

If so, by what margin? Obviously, if you were just flipping coins, and

measured the results once, you’d get 50% positive correlation, twice and

you’d get 25% correlation, ten times and you’d get 0.1% correlation, and

you’d be at 911 out of a million. So, how much better than that are we

talking about?

Look at Figure 2b in the Ursin paper. You are always doing this against

some background, looking for a statistically significant peak.

Regards

Marshall