Thank you for this very interesting topic ! Please play this Youtube clip -- it was taken in a movie theater in 1980 when The Empire Strikes Back first came out. it seems to record a moment of a Mandela change . Listen closely at 0:52 -- Darth Vader says "NO-LUKE I am your father..." .To me it is like a moment when two time threads crossed, before separating forever.
In the german dubbed version, the voice actor says "Nein, ich bin dein Vater", which translates to "No, I am your father." The way he pronounces the "Nein" (No) is very distinctive, stretching the word like people do when they want to emphasize it. And that's how I remember it. Here's the german version for comparison:
But it should also be mentioned that James Earl Jones, the english voice actor of Darth Vader, remembers it differently: