...or some philosophy

alright, take a nanomolecular matter compiler and create an exact duplicate of me, right down to the individual atom, including my nervous system. Out pops someone exactly like me, who has all the same memories as me, who, for all intents and purposes was me until a second ago when he stepped out of a matter compiler and i didn't.
for the moment before our experiences diverge, we are exactly identical in every respect but one: I subjectively experience being me, whereas I presumably don't experience being this other me. That's the difference I'm interested in.