Quantum Computing Could Change Everything ... Someday

There is a great deal of excitement in the scientific community and industry about the transformational possibilities of quantum computing. Some expect it to change our world. Tech giants such as Google, IBM, Honeywell, Microsoft, Rigetti, IonQ, and Alibaba are vying to build the most powerful quantum computer. The U.S. government and other national governments are funding quantum computing projects in their countries.

Some companies have even claimed to have already built a quantum machine capable of quantum supremacy. What is quantum supremacy? The term refers to the capability of a programmable quantum computer to solve a mathematical problem that a traditional computer is functionally incapable of solving. Most observers feel that we're not quite there yet.

In the early 1980s, physicist Paul Benioff put forward a theoretical demonstration of a quantum mechanical prototype of the Turing machine. In 1982, Richard Feynman published a paper in which he suggested that quantum systems could be simulated only on quantum computers. Traditional or "classical" computers, he stated, are not capable of quantum simulations.

In 1994, Peter Shor created an algorithm that could break cryptographic codes. In 1996, Lov Grover devised an algorithm for rapid searches of vast and unstructured datasets. These algorithms can work only on a universal quantum computer. Back then, there were no quantum computers.

Since the 1990s, researchers have been working on developing a powerful quantum computer. In 1998, researchers at the University of Oxford said they had developed the computing capability to process data using two qubits (a qubit, or quantum bit, is the basic unit of quantum information). IBM's 14th quantum computer currently has 53 qubits. It is the company's most powerful quantum computer yet.

Other companies, such as D-Wave, Rigetti, and Alibaba have infused the power of traditional computing with quantum potential by developing so-called hybrid classical-quantum systems.

It's not classical, it's quantum

Classical computers use bits or transistors, which represent 0 or 1, to process information. All the data processed by classical computers consists of strings of these digits, a paradigm that has become embedded in the collective subconscious so firmly that "ones and zeros" is a default pop cultural shorthand for data, computers, and technology alike.

Quantum computing technology processes information in a different way. This technology is based on the fundamentals of quantum mechanics. Quantum computers use quantum bits (qbits), which are subatomic particles, to process information. Qubits could have any value from 0 to 1, but they can also have 0 and 1 simultaneously. This enables a quantum computer to process a vast number of inputs at the same time.

Quantum computers work on the basis of natural phenomena or states of matter as defined in quantum mechanics. These quantum states are known as superposition and entanglement. The capability of a qubit to be 0 and 1 at the same time is known as superposition. It is this capacity that is at the core of quantum computing's potential to generate exponentially greater computing power than classical computing.

The power of a quantum computer depends on the number of qubits it can use. The more qubits a quantum computer has, the more powerful it is. Researchers believe that a reliable quantum computer will be able to process huge data sets and perform complex computations with far greater efficiency than classical computers.

So far, there are three types of quantum computing. These are quantum annealing, quantum simulation, and universal quantum computing.

Fueling impressive advances

There is tremendous excitement about the possibility of quantum computing to drive advances across multiple branches of science and industry. Quantum computing's potential for optimization, probability computation, and molecular simulation could lead to advances in materials science, pharmaceuticals, and financial probability.

Researchers and businesses believe quantum computing can be applied to spur innovation and transformation in many industries, including healthcare, cybersecurity, agriculture, financial services, automobiles, and cloud computing, to name a few. This is because of quantum computing's ability to generate optimum solutions to complex mathematical problems and to simulate molecular behavior.

In the healthcare industry, pharmaceutical companies are applying quantum simulation to examine and compare the effect of different drugs on proteins, aspiring to develop the most effective drugs for different ailments. Researchers believe that quantum simulation can also be applied to accelerate the process of genome sequencing with a view to formulating personalized medication for each patient.

Quantum computing can lead to significant improvements in cybersecurity. Powerful quantum computers, when they are built, will be capable of breaking cryptographic codes and encrypting electronic communications using a method known as quantum encryption.

Quantum encryption relies on the concept of transmitting data in the form of entangled photons over distances. The main advantage of quantum encryption over existing modes of encryption is the simultaneous alerting capability in the event of an interception.

In the automobile industry, companies, such as Daimler and Volkswagen, are using quantum simulation to simulate and analyze models of numerous possible chemical compounds in the hope of developing better batteries for electrical vehicles.

Quantum computing's ability to consider multiple options at once and find the optimum solution is encouraging companies to discover the best travel routes for cars, cabs, and taxis in different cities so as to ease traffic congestion. Airbus is using quantum computing to find the most fuel-efficient paths for aircraft.

Companies, such as Google, IBM, and QCWare are working on cloud computing projects with the purpose of developing a simpler and more streamlined approach to programming and providing economical and easy access to quantum computers.

The quantum future is all about potential

Presently, quantum computing technology is at the experimental stage; what we hear about is the promise and potential of quantum computing. The commercial quantum computing industry is still nascent.

Researchers and engineers are working toward building large-scale quantum machines for practical use. We have not reached a point where quantum computers are commercially viable and real-world problems are being solved by quantum computers.

It is difficult to engineer, manufacture, program, and manage quantum computers. They are far more error-prone than classical computers. This is because faults arise due to noise and loss of coherence, which cause data corruption. Qubits are very hard to maintain. The quantum state of qubits is extremely susceptible to changes in temperature and other vibrations.

This is why Google, IBM, and Rigetti Computing maintain the superconducting circuits that run their quantum computers at near-zero temperature, and IonQ uses vacuum chambers to protect their qubits. Even so, the quantum computers in use today are not reliable because the noise and error causes loss of information within seconds.

Researchers and engineers are working on building stable, error-tolerant quantum computers that can be used on a relatively large scale to solve practical problems, but it is unlikely to happen in the next few years. No one knows precisely when quantum computers will achieve commercial viability, but most experts don't expect to see large-scale quantum computers in use in the next 10 years.

The quantum present is all about research

Quantum computers are currently being used primarily for research and education. Some large companies are experimenting with in-house quantum computing projects. Google uses a quantum system developed by D-Wave Systems in the Quantum Artificial Intelligence Lab (QuAIL), hosted by NASA and the Universities Space Research Association.

Other corporations that are exploring quantum computing include Microsoft, Intel, and Hewlett Packard. A few companies, such as IBM, IonQ, D-Wave, and Rigetti, offer access to their quantum hardware via the cloud, for those who want to write programs. According to some experts, we could see some progress in solving optimization problems in the near future.

Quantum computing technology hasn't developed to a point where it offers a time- or cost-based computational advantage in comparison with classical computing. It's unlikely that quantum computers will replace classical computers any time soon. Classical computers will continue to be in use because they are capable of processing everyday tasks, easily accessible, and economical.