Two Bits vs. Qubits—The Age of Quantum Computing
“The history of the universe is, in effect, a huge and ongoing quantum computation. The universe is a quantum computer.”
—Seth Lloyd, MIT Professor
From inventing the wheel to discovering gravitational waves, mankind and its achievements have come a long way. We are now being led into the new era of technology—quantum computing. With a far more complex working than our classical computers, quantum computers can perform operations thousands of times faster than their classical counterparts, pushing the boundaries of computation as we know it today.
With the intricate developments in the field of quantum mechanics and the discovery of inherent properties like superposition and entanglement, the inception of quantum computing algorithms and mechanics began with Paul Benioff, Yuri Magnin, and Richard Feynman’s ideas in the 1980s. Following this, David Deutsch proposed his idea of a universal quantum machine, also called the universal Turing machine, in 1985. However, a major interest sparked in the computing world with Peter Shor’s invention of a factorization algorithm in the 1990s, shifting the interest from purely theoretical to practical quantum computing. Researchers reckoned any quantum computer that could solve Shor’s algorithm would be able to break the current cryptography techniques in seconds. With enough interest and potential garnered, work on quantum computation flourished and is still ongoing to this date.
Conventional computers used today are built with transistors and diodes and deal with classical bits of information, which can exist in a state of either on or off (the binary states 1 or 0). Quantum computers, however, deal with quantum bits, or qubits, which use the quantum mechanical properties of superposition and entanglement, and can exist in a superposition state of 0 and 1. This property allows n qubits to store 2 raised to the power of n classical bits of information, as opposed to n bits of information as in classical computers, making their performance capabilities thousands of times faster. However, quantum computers would not carry out simple operations like multiplication significantly faster than classical computers. They are useful when an algorithm is correctly applied to use the quantum parallelism and then can carry out an operation in a fraction of the time a classical computer would take. In the words of Simon Bone and Matias Castro from their essay ‘A Brief History of Quantum Computing’: “Shor’s algorithm allows extremely quick factoring of large numbers—a classical computer can be estimated at taking 10 million billion years to factor a 1000-digit number, whereas a quantum computer would take around 20 minutes”.
In 2011, a Canadian quantum computing company, D-Wave, introduced their product D-Wave One, claiming it to be the world’s first ever commercial quantum computer. The company further went on to announce developments in their products, overcoming more obstacles in the succeeding years. As of 2017, multiple companies have displayed their developments in the quantum computation sphere—D-Wave Systems has announced commercial availability of their D-Wave 2000Q quantum annealer, IBM has revealed a working 50-qubit quantum computer, Intel has developed a 17-qubit quantum chip, and Microsoft has announced an unnamed quantum programming language, integrated with Visual Studios. The field has certainly witnessed striking developments, with Google and NASA reporting that a D-Wave System 2 with 1097 qubits outperformed supercomputers by more than 3,600 times and personal computers by 100 million times. The most recent developments are regarding a ‘flip-flop’ quantum computer, which is being regarded as a major breakthrough in quantum computer design.
Simon Bone, in his aforementioned essay, talks about the futuristic prospects in developing quantum liquids and mentions hopes for advances in the quantum bits techniques. It is speculated that quantum computing may even find an application in bettering current artificial intelligence techniques. Albeit difficult to implement and fragile due to the reliance on quantum mechanics, the power of quantum computation may go on to surpass current limitations.