Suppose you have two arbitrarily powerful participants who don't trust each other. They have access to bit commitment (e.g., sealed envelopes containing data that one player can hand to the other but that can't be opened until the first player gives the second a key). Can you use this to build an oblivious transfer protocol. Is this true even if the players agree to open all the envelopes at the end to detect cheating (e.g., after the poker hand is played, everybody agrees to reveal their cards)?
I assume that you can't get oblivious transfer out of bit commitment, because oblivious transfer is cryptographically universal, and I can't find any references that say bit commitment is, but is there a proof somewhere that you can't do it?
Finally, has anybody looked at the problem if the players are quantum?