I believe that the digital currency will dominate, but it will not make the papers disappear
Paper money will never disappear not in this century, in before the increase in the dominance of internet which makes the use of electronic money as such, it has not even reduce the amount of paper notes being printed by the Central Bank. Paper money has being with us for ages and centuries and for any kind of currency to replace it means it has to be around if not that long then close to that or else, the worse that will happen is that they both co-exist.
Actually paper money is now starting to go digital. Just look at China it will release its prototype fiat digital currency this coming September. This signals a new leap in the banking system. Soon other countries will turn into a cashless society like china. Paper money will soon be history when fiat digital currency hits the road.