When you flip a coin, you’re used to thinking about the outcome in terms of heads or tails. But have a chat over coffee with a quantum physicist and you’ll probably come away convinced that a third scenario is possible—that heads and tails can occur at the same time; it happens while the coin is in the air.
To use the parlance of quantum physics, the coin can be said to be in a ‘superposition’ of states, and it turns out this fundamental principle holds the key to realising a quantum leap in computing. The computers that we know and use today perform their complex operations using binary digits, or bits. These bits can only take on the values of 0 or 1, but not both. The binary nature of classical computers thus places an upper limit on the complexity of calculations that can be performed on them.
These limitations look set to be broken with quantum computers running on qubits—quantum bits that can be in a superposition of 0 and 1. A quantum computer of 50 qubits, for instance, could perform 250 calculations in a single step, far surpassing the computational power of classical computers.
A super proposition
“In the past eight to ten years, we’ve seen a huge number of publications and patents in the realm of quantum computing,” said Mr Claus Helbing, Managing Director of Boston Consulting Group (BCG) Digital, at the Hello Tomorrow Singapore Regional Summit on 7 November 2019.
The talk was a timely update on the field of quantum computing, as Google just recently announced that it had achieved quantum supremacy—the use of a quantum computer to solve a problem that cannot be solved by a classical computer. Google is but one of many industry players investing millions of dollars into quantum computing research, said Mr Helbing, adding that “this clearly shows that the topic is getting bigger now, moving away from being a niche area in academia to something that’s at the heart of what many companies think about.”
Some sectors that stand to gain from the immense computing power of quantum computers include the automotive and aeronautical industries, which need to perform computationally intensive fluid dynamics simulations to optimise the design of vehicle parts.
“Similarly, in the area of pharmaceuticals and drug design, the simulation of molecules is something that can be particularly difficult for classical computers to figure out, especially when you’re dealing with very complex large molecules,” said Dr Alice Mahoney, Junior Consultant, Technology Advantage, BCG. “Using quantum circuits, scientists have predicted that we will be able to do much more efficient drug design,” she noted.
Securing a digital future
Despite their usefulness, quantum computers may pose a cybersecurity risk.
“So much of modern encryption—public key, RSA-type encryption—is based on the fact that it is very difficult for classical computers to efficiently factor large numbers into their primes. However, it’s been theoretically demonstrated that quantum mechanics can provide a solution to this… in much more feasible amounts of time with enough quantum resources,” said Dr Mahoney.
As Singapore moves towards its smart nation vision and continues to pursue its digitalisation ambitions, the government is not waiting around for a quantum computing-driven security breach to occur. The Infocomm Media Development Authority (IMDA) announced in June 2018 that it was partnering with the National University of Singapore’s Centre for Quantum Technologies to pursue advanced encryption tech using quantum physics.
The partnership also included the rollout of workshops and training programmes for government agencies and the industry to build capabilities in quantum technologies. IMDA is also exploring possible quantum key distribution trials with local industry players to better understand the potential challenges in implementing a quantum-safe network.
With companies like Google already claiming quantum supremacy, these measures could not come sooner.
“We believe that starting in probably five to ten years, we will reach a stage where quantum computing will be able to solve specific problems that we haven’t been able to solve before, and we will see the first benefits of the technology,” said Mr Helbing. “Having said that, it’s important to note that quantum computing is not meant as a replacement for traditional computing — it’s an addition [to our problem-solving toolkit].”
By Jeremy Chan