Professor Emmanual Haven, Professor of Economics

Quantum Computing

There is a lot of talk about the possible existence of a so-called quantum computer. The popular science press often covers articles on that topic, and although many important universities have allocated very important research funds to the development of said computers, it may well be the case, that at present no such computer really yet exists (or at least it is not public knowledge).

The quantum computer idea has become identified almost uniquely so far, at least in the popular press, with the idea that using such computers would allow for the creation of codes which would make ultra-sensitive communication ultra-safe. The idea is based on three key principles from the quantum world: superposition, observation altering a state and entanglement. The binary - one-zero code system upon which classical computers work, is now extended to one-zero and a superposition of one-zero. 

Another key property which is at play here, is the fact that observation alters the state in the quantum world. So, any intercepted code will be altered, since it is observed. Finally, entanglement, which could be loosely defined as ‘super strong correlation’, indicates that the same information between parties can exist instantaneously even though when both parties are separated from each other on very large distances. It is well known that the blockchain technology relies upon classical cryptography. With the three properties mentioned above, a quantum block chain would be made much safer. Finally, to come back to the statement we made at the beginning: quantum computers do exist, but it is a matter of degree. The key question is: how many qubits can the computer work with? The more qubits, the more powerful the ‘quantum’ computer will be.

Written by Professor Emmanual Haven, Professor of Economics - May 2019