In the future far from now the paper money will disappear because everything would be digital and nothing will go with paper things anymore.
Its just a matter of time in my eyes.
I do believed that in the future paper money will disappear, and this is also written in the bible that paper money/money will no longer be useful at all in all countries.
Its really hard to believe that paper money will fully disappear in future as that seems to be unreal to me as there will be many people who will follow the traditional ways of spending their money and will never get into digital world by using bitcoins for making their purchases.