Although the first computer was invented near the start of the 19th century, it was not until the latter half of the 20th century that computing technology came to be an indispensable part of daily life. Now, as we approach the second quarter of the 21st Century, a growing number of technologists are predicting that this century will be dominated by a new form of computation, known as quantum computing.
“Quantum computing is anticipated to be an industry disruptor,” Heather West, senior research analyst for Infrastructure Systems, Platforms and Technologies at market research firm IDC, predicts. “Many organizations are already experimenting with its potential today to gain a competitive advantage tomorrow.”
As traditional computing has entered the mainstream, the concept of storing information as bytes of data has become well-known. This process transforms information into 0s and 1s, switching transistors either on or off, and is the basis for all traditional computing power.
Quantum computers promise a whole new approach to creating algorithms that instead harnesses the power of quantum states, creating a new type of machine that is capable of much more powerful calculation.
“Quantum computing applies the properties of quantum physics to the processing of information,” Dr. Julie Love, quantum lead at Microsoft, explains “This exponentially faster and more powerful computing will accelerate the development of new sustainable materials, improved healthcare, methods to address food production, and combat climate change.”
Quantum states are unique probability distributions predicted by fundamental physics that are often portrayed as paradoxical or illogical. Concepts such as Schrodinger’s Cat – the inability to know the state of a system before measuring it – superposition, interference, and entanglement have all perplexed philosophers for decades, but scientific experiment has shown time and again that they have real world applications.
By harnessing these strange, sub-atomic states of nature, computer designers are able to create processing power that is capable of acting in parallel rather than sequence. Typically using the manipulation of neutrons, photons, electrons and protons to perform calculations, these computers are freed from the constraints of using silicon circuits – but the quantum states they rely on are notoriously fragile.
Whereas a traditional computer relies on digital bits – the 1s and 0s that make up computer code – a quantum computer utilises ‘qubits’, a two-state system that can exist in multiple superposed states at the same time. Despite the promise of these states, it has so far proven difficult to construct computers with more than a few qubits before the system collapses. This compares with the hundreds of millions of transistors per square millimetre on a traditional chip.
“The stage of quantum computers now is something like classical computing in the late 1980s,” says Sara Metwalli, a quantum-computing researcher at Keio University in Tokyo. “Most of the work done now is to prove that quantum, in the future, may have the ability to solve interesting problems.”