Newbie question. AFAIK, each US banknote has a unique serial number. Is the same true for bitcoin? Does each bitcoin have a unique identifier, regardless who owns it? Does each satoshi have a unique identifier?
This is true only for cash banknotes, but most of the dollars in circulation now is virtual and digital numbers on screen, so there is no real identifiers there.
There is no such thing in bitcoin, but you can identify history and origin of coins on blockchain, that is why governments and regulators can blacklist bitcoin addresses and connected coins.