January 15, 2013 – Last year two physicists received the Nobel Prize for their achievements on the area of quantum mechanics. Although ‘quantum money’ – based on quantum mechanic – was conceived as far back as 1983, only recently researchers are making progress on how such money could be really created.
The first reason above all why applying quantum mechanics with money would be the fact that quantum money could not be counterfeited. Behind this stands a central point in quantum mechanics: the no-cloning theorem. The qubits, a unit of quantum information, that inheres to any object cannot be even measured without altering them. Hence any manipulation would lead to an alteration of the banknote’s or token’s qubits. On the one hand this promises a guarantee against any counterfeit attempt. On the other hand that is the problem: how to realize something that sooner or later must necessarily be measured – by the bank for instance – without destroying it or changing it in a way that it looses it’s value?
Now scientists believe that it may be possible to measure only a part of the qubit’s information in order to not manipulate the overall properties while permitting an external control.
That sounds very complicated and, indeed, it is. Although, now there are some concrete ideas and projects studying this possibility of realizing quantum money, nobody knows when that money could become reality. Maybe in some decades – maybe even never. So for the time being we should not neglect working on how to prevent counterfeiting the existing money.