Quantum computing has the potential to revolutionise our computing capabilities, and IBM’s recent announcement of their Q System One suggests that huge strides are being made towards utilising them for practical purposes in business environments. The Q System One is “the world’s first fully integrated universal quantum computing system designed for scientific and commercial use” according to the company. Elsewhere there are quantum computers which can be accessed through the cloud, but only for research-lab purposes. The key aspect of the nine-foot-tall system which differentiates it from previous others is its reliability, a huge issue generally for quantum computers, as chips need to be maintained at very low temperatures (as low as 0.01 Kelvin) and electrical and physical fluctuations must be minimised.
A computer such as the Q System One won’t be appearing in Currys PC World anytime soon.
Quantum computers undergo calculations in a different way to classical computers, which are reaching their limits as transistors become smaller and smaller. Using the quantum mechanics feature of superposition, qubits (quantum bits) which carry information essentially exist in two states simultaneously, rather than as binary values, as with bits in classical computers. These states may take the form of any two-level system, commonly electron spin, and can also be ‘entangled’ with other qubits, leading to behaviour together as a system (this has no classical analogue). These phenomena mean the power of the computer is increased exponentially compared with what we currently work with.
Dr. Talia Gershon, Senior Manager of Quantum Research at IBM, says “we’re not envisioning quantum computers completely replacing classical computers anytime soon. We think that quantum computing is going to be use to accelerate things that are really hard for classical machines”. This includes developments in areas such as drug discovery and machine learning. Perhaps the most interesting use is in probing the very quantum mechanical nature of chemical bonding: using quantum to simulate quantum, mimicking other electrons rather than attempting to represent them with complicated formulae.
The use of the word ‘commercial’ in IBM’s announcement could be perceived as misleading: a computer such as the Q System One won’t be appearing in Currys PC World anytime soon. The collaboration within the IBM Q Network, which includes a community of Fortune 500 companies and startups, explain its ‘commercial’ nature, and the list of those interested in harnessing the power of this technology is only going to grow.
In reality we are still quite a way away from seeing these types of computers in widespread use. Competition between companies like IBM, Google, Intel and D-Wave Systems means the boundaries are constantly being pushed, but as of now the best systems can handle up to a couple of thousand qubits, whereas some of the algorithms we may want to run would require millions. They’d need to be performed by a ‘fault-tolerant’ quantum computer: one where issues such as errors arising from quantum decoherence caused by the sensitivity to external fluctuations are corrected for faster than they’re created. If, in the next decades, these issues are solved, some of the most complex challenges we face will suddenly become a piece of cake.