I think satoshi should popup and accept Nobel prize
How would we know it's really him and not an impostor?
I agree with that. How do you prove hes "real" Satoshi especially if he is dead. Also what happens if Satoshi is group consists of a couple of people? Some maybe want to take it and some dont want to disclose their identity and risk their life.
Anyway, I dont think he/they will show up to take the Nobel if he/they deserve it.
I don't think we could ever be 100% sure it's him but I believe it should be possible to filter out 99.9% of impostors just by analyzing Satoshi's past interactions with the world along with other data about him that are known to be true. I highly doubt the real Satoshi will show up for the prize if ever it was awarded to him.