
Quantum Computing
Quantum computing is a rapidly advancing field of computer science research that is expected to enter commercial application in the midtolate 2020s. By this time, quantum computers will outperform traditional computers at certain tasks that are likely to include molecular and material modelling, logistics optimization, financial modelling, cryptography, and pattern matching activities that include deep learning AI. This page provides a nontechnical overview of quantum computing pioneers and developments, and provides support for my Quantum Computing Update videos published in 2020, 2019, 2018 and 2017, the most recent of which is embedded below. Note that the 2017 video explains more about different quantum computing technologies, while the 2018, 2019 and 2020 QUANTUM BASICSTraditional or 'classical' computers are built from silicon chips that contain millions or billions of miniature transistors. Each of these can be turned "on" or "off" to represent a value of either "1" or "0". Conventional computers subsequently store and process data using "binary digits" or "bits". In contrast, quantum computers work with "quantum bits" or "qubits". These can be represented in hardware in many ways  for example by using the quantum mechanical properties of superconducting electrical circuits, or individual trapped ions. Due to the peculiar laws of quantum mechanics, qubits can exist in more than one state  or ‘superposition’  at exactly the same point in time. This allows a qubit to assume a value of ‘1’, or ‘0’, or both of these numbers simultaneously. In turn, this enables a quantum computer to process a far higher number of data possibilities than a classical computer and to perform massively parallel processing. It also means that every qubit added to a quantum computer increases its power exponentially. The fact that qubits are more 'smears of probability' than definitive, blackandwhite certainties is exceptionally weird. Flip a coin, and it cannot come up both heads and tails simultaneously. And yet the quantum state of a qubit can in some senses do just that. It is therefore hardly surprising that renowned nuclear physicist Niels Bohr once stated that 'anyone who is not shocked by quantum theory has not understood it!' In addition to assuming superpositions, qubits can become ‘entangled’. ‘Entanglement’ is another key quantum mechanical property, and means that the state of one qubit can depend on the state of another. This is useful and powerful, as it means that observing one qubit can reveal the state of its unobserved pair. Creating and manipulating qubits is very hard indeed. Many of today's experimental quantum processors exploit the quantum phenomenon that occur in superconducting materials, and hence need to cooled to almost absolute zero (around minus 272 degrees celsius). Significant shielding against background noise is also required, and even then performing computation using qubits requires significant error correction. Indeed, a grand challenge in quantum computing is the creation of a truly faulttolerant machine. QUANTUM PIONEERSCompanies currently developing quantum computer hardware include IBM, Alibaba, Microsoft, Google, Intel, DWave Systems, Quantum Circuits, IonQ, Honeywell, Xanadu and Rigetti. Many of these firms work in conjunction with major university research teams, and all continue to accrue significant progress. The following provides an overview of the work of each of these pioneers.
IBM has been working to develop a quantum computer for over 35 years. It is also making significant progress, with several operational machines. According to the IBMQ website, while 'today quantum computing is a researcher’s playground', in five years 'it will be mainstream'. As IBM goes on to explain 'in five years, the effects of quantum computing will reach beyond the research lab. It will be used extensively by new categories of professionals and developers looking to this emerging method of computing to solve problems once considered unsolvable'. In 2016, IBM launched a website called the IBM Q Experience that made a 5 qubit quantum computer publicly available over the Internet. Since this time, this has been joined by a second 5 qubit machine and a 16 qubit machine, both of which are available for anybody to experiment with. To help those wishing to learn about and develop quantum computing, IBM offers an open source quantum computing software framework called Qiskit. In addition to the above, in November 2017 IBM announced that two 20 qubit machines were being added to its quantum cloud. These can be used by clients who are signedup members of the IBM Q Network. This IBM describes as 'a worldwide community of leading Fortune 500 companies, startups, academic institutions, and national research labs working with IBM to advance quantum computing and explore practical applications for business and science'. Also in November 2017, IBM announced that it had constructed a 50 qubit quantum processor, which remains its most powerful quantum hardware to date. In January 2019, IBM announced unveilled its IBM Q System One as the "world's first integrated universal approximate quantum computing system designed for scientific and commercial use. This modular and relatively compact system is intended to be used outside of a laboratory environment. You can learn more about the IBM Q System One in the this press release.
Another tech giant that is working hard to make quantum computing a reality is Google, which operates its Quantum AI Laboratory. In March 2017, engineers Masoud Mohseni, Peter Read and Hartmut Neven who work at this facility published this article in Nature in which they contented that shortterm returns from quantum computing 'are possible with the small devices that will emerge within the next five years', so supporting IBM's view of the timescale for commercial quantum computing to arrive. Google's early with in quantum computing involved the use of a machine from Canadian pioneer DWave Systems. However, the company is now rapidly developing its own hardware, and in March 2018, announced a new 72 qubit quantum processor called 'Bristlecone'. In June 2019, the director of Google's Quantum Artificial Intelligence Lab, Hartmut Neven, revealed that the power of its quantum processors is now increasingly at a doubly exponential rate. This has been termed “Nevan’s Law”, and suggests that we may reach the point of quantum supremacy  where a quantum computer can outperform any classical computer  by the end of 2019. In October 2019, an engineering team from Google published a paper in Nature in which they claimed to have achieved quantum supremacy. Specifically, the Google scientists had used a quantum processor called Sycamore to sample the output of a pseudorandom quantum circuit. Sycamore took about 200 seconds to sample one instance of the circuit a million times. In comparison, the Google team estimated that a classical supercomputer would take about 10,000 years to perform the same calculations. As the team went on to conclude: "quantum processors based on superconducting qubits can now perform computations ... beyond the reach of the fastest classical supercomputers available today. To our knowledge, this experiment marks the first computation that can be performed only on a quantum processor. Quantum processors have thus reached the regime of quantum supremacy." The Google announcement was big news, but soon controversial. Not least IBM published a blog post in which they stated that the computations in Google’s experiment could be undertaken on a classical computer in twoandhalf days, rather than 10,000 years. And as IBM went on to contend "Because the original meaning of the term ‘quantum supremacy,’ as proposed by John Preskill in 2012, was to describe the point where quantum computers can do things that classical computers can’t, this threshold has not been met."
Over in China, the main web giant is Alibala, not Google. And in July 2015, Alibaba teamed up with the Chinese Academy of Sciences to form the 'CAS  Alibaba Quantum Computing Laboratory'. As its Professor Jianwei Pan explained at the time, this has the mission to 'undertake frontier research on systems that appear the most promising in realizing the practical applications of quantum computing . . . so as to break the bottlenecks of Moore's Law and classical computing'. You can visit the website for the lab here. Like IBM, Alibaba has now made an experimental quantum computer available online. Specifically, in March 2018 the Chinese ebusiness giant launched its ‘superconducting quantum computing cloud’ to provide access to an 11 qubit quantum computer. This was developed with the Chinese Academy of Sciences, and allows users to run quantum programs and download the results.
As you may anticipate, Microsoft is also keen to get in on the quantum computing action, and is working with some of the world's top academics and universities to try and make this happen. To this end, Microsoft has set up several 'Station Q' labs, such as the one located at the University of California. In February 2019, Microsoft also announced the Microsoft Quantum Network to formalize its range of partnership coalitions. A key element of Microsoft's strategy is the development of quantum computers based on 'topological qubits', which it believes will be less prone to errors (hence requring fewer final system resources to be devoted to error correction). Microsoft also believes that topological qubits will be easier to scale to commercial application. Indeed, according to May 2018 article in Computer Weekly, Microsoft’s vicepresident in charge of quantum computing believes that it could have commercial quantum computers on its Azure cloud platform just five years from now. On the software side, in December 2017 Microsoft released a preview of its quantum computing development kit. This is free to download, and includes a programming language called Q#, and a quantum computing simulator. In May 2019, Microsoft additionally reported that it is going to open source the development kit. And in May 2020, Microsoft announced its Azure Quantum cloud computing service.
As you may also expect, as the world's leading producer of microprocessors, Intel is working to develop quantum computing chips. To this end, it is also hedging its bets by taking two different research approaches. One of these strands is being conducted in conjunction with the leading Dutch quantum computing pioneer QuTech. In November 17, Intel announced the delivery of a 17 qubit test chip to its partner in the Netherlands. Then, in January 2018 at CES, it further announced the delivery of a 49 qubit test quantum processor called 'Tangle Lake'. Intel's second quantum computing reseach strand is taking place entirely inhouse, and involves the creation of processors based on a technology called 'spin qubit'. This is a significant innovation, as spin qubit chips are manufactured using Intel's traditional silicon fabrication methods. In June 2018, Intel reported that it had begun testing a 26 spin qubit chip. Already, the qubits on Intel’s spin qubit wafers are only about 50 nanometers across, or 1/1500th the width of a human hair. This means that, maybe a decade from now, Intel could be manufacturing tiny quantum processors containing thousands or millions of qubits. Unlike conventional CPUs, these would need to be supercooled to almost absolute zero. But the potential is truely breathtaking. And according to Intel's quantum computing web pages, the company is targeting productionlevel quantum computing within ten years, and anticipates that the technology will start to enter its “commercial phase” around 2025.
DWave Systems is a pureplay pioneer based in Canada, and way back in 2007 demonstrated a 16 qubit quantum computer. In 2011, it then sold a $10 million dollar, 128 qubit machine called the DWave One to Lockheed Martin. In 2013, DWave next sold a 512 Qubit DWave Two to NASA and Google. By 2015, DWave even broke the 1,000 qubit barrier with its DWave 2X, and in January 2017 sold its first 2,000 qubit DWave 2000Q to cyber security firm Temporal Defense Systems. Reading the above list of achievements, you may have concluded that DWave has to be the world's leading quantum computing pioneer. It is, after all, the only company ever to sell a quantum computer. However, notwithstanding all of the aforementioned milestones, DWave’s work remains controversial. This is because their hardware is based on an 'adiabatic' process called ‘quantum annealing’ that other pioneers have dismissed as ‘restrictive’ and ‘a dead end’. IBM, for example, uses a ‘gatebased’ approach to quantum computing that allows it to control qubits in a manner analygous to the manner in which a transistor controls the flow of electrons in a conventional microprocessor. But in a DWave system their is no such control. Instead, a DWave quantum computer takes advantage of the fact that all physical systems tend toward minimum energy states. So, for example, if you make a cup of tea and leave it standing, when you come back it will be cold as it will have declined to a more minimal energy state. The qubits in a DWave system also do this, and so what DWave does is to use its hardware to solve optimization problems that can be expressed as ‘energy minimization problems’. This is indeed restrictive, but still allows the hardware to run certain algorithms far faster than a classical computer. You can view a great video in which DWave explain their approach to quantum computing here. In August 2016, this paper in Physical Review X reported that certain algorithms ran up to one hundred million times faster on a DWave 2X than on a singlecore classical processor. One of the authors of this research also happened to be Google’s Director of Engineering. This all said, the jury remains out on the value of DWave's work to the general development of our quantum computing future. The above noted, DWave continues to push forward significantly its variant of quantum computing. For example, in October 2018, it launched a cloudbased, quantum application environment called Leap. This provides realtime access to a DWave 2000Q quantum computer, and in March 2019 was expanded to provide access in Japan and across Europe.
Another quantum computing pureplay is a startup called Rigetti. The company already has over 120 employees, and has made a 19 qubit quantum computer available online through its developer environment called Forest.
Another quantum computing startup is Quantum Circuits, which was established by leading quantum computing professor Robert Schoelkopf and other colleages from Yale University. The company has raised $18 million of venture capital, and plans to beat the computing industry giants in the race to make a viable quantum computer.
IonQ is a pureplay pioneer in trappedion quantum computing. The company claims that its technology 'combines unmatched physical performance, perfect qubit replication, optical networkability, and highlyoptimized algorithms' in order to 'create a quantum computer that is as scalable as it is powerful and that will support a broad array of applications across a variety of industries'. If you want to learn more, IonQ's technology page is an excellent learning resource
Xanadu is developing photonic quantum computing by designing and integrating 'quantum silicon photonic chips into existing hardware to create truly fullstack quantum computing'. As the company further notes, compared to other qubit technologies, 'photons are very stable and are almost unaffected by random noise from heat. We use photonic chips to generate, control, and measure photons in ways that enable extremely fast computation'.
Another pioneer of trappedion quantum computing is Honeywell, a company with a long heritage in business computing. In June 2020, Honeywell announced that it had created the world’s highest performance quantum computer. Others may take a different view. But regardless, this is another important development  particularly as it has been reported that J.P. Morgan Chase is already experimenting with its system to develop financial services applications including fraud detection and AI trading.
Amazon has not announced that it is developing quantum computing hardware or software. However, on December 2nd 2019, it did launch a range AWS quantum services. These include Amazon Bracket, which allows scientists, researchers and developers to begin experimenting with quantum computers from multiple hardware providers. Specifically, customers can access hardware from Rigetti, IonQ and DWave Systems, which means that they can experiment with systems based on three different qubit technologies. In addition to Bracket, Amazon also launched the Amazon Quantum Solutions Lab. This is intended to help companies to ‘get ready for quantum computing’ by allowing them to work with leading experts. So a key thing that Amazon is doing with its quantum computing offerings is to act as a cloud broker. QUANTUM COMPUTING SOFTWARE DEVELOPERSEven the best quantum computer hardware is no use without appropriate software, and many of the above quantum hardware pioneers are developing their own. However, there are also already a growing number of quantum computing software pioneers, as follows.
1QBit parters with large companies and "leading hardware providers to solve industry problems in the areas of optimization, simulation, and machine learning". The company develops software for both classical and quantum processors, although the name of the company indicates their primary focus.
Cambridge Quantum Computing develops quantum computing software to solve the "most intriguing challenges" in areas including quantum chemistry, quantum machine learning and quantum cybersecurity. Clients include companies in "some of the world's largest chemical, energy, financial and material science organisations" who are trying to harness the power of quantum computing.
QC Ware develops "enterprise software and services for quantum computing", with clients including Airbus, BMW and Goldman Sachs, and hardware partners including AWS,DWave Systems, Google, IBM, Microsoft and Rigetti, as detailed above.
QSimulate is developing software to "bring the power of quantitative simulations to solve pressing problems in the pharmaceutical and chemistry spaces".
Rahko is creating software that is intended to use quantum machine learning (quantum AI) to solve problems in quantum chemistry.
Zapata Zapata works with its clients to develop quantum computing software to solve compulationally complex problems in fields including chemistry, finance, logistics, pharmaceuticals, engineering, and materials. QUANTUM COMPUTING USERS AND APPLICATIONSAs noted at the start of this article, anticipated applications for quantum computing include molecular modelling (also known as molecular modelling or quantum chemistry), logistics optimization, financial modelling, cryptography, and pattern matching activities such as deep learning artificial intelligence. Already some large businesses are also actively reseaching exactly what quantum computing may do for their research and development, their products and services, and thier bottom line. As so below I just a few examples. Daimler is working with both IBM and with Google to investigate how quantum computers may be used in logistics to help optimize vehicle delivery routes, or the flow of parts through factories. The company is also researching how quantum computers could be used to simulate chemical structures and reactions inside batteries, and so assist in the improvement of electric vehicles. Also in the automotive sector, Volkswagen has been working with both Google and DWave Systems to see how quantum computers may assist with traffic flow optimization problems, as well as to help it develop better batteries. Over in the financial sector, JPMorgan is working with IBM to explore how quantum computers may assist with trading strategies, portfolio optimization, asset pricing and risk analysis. Similarly Barclays is also participating in the IBM Q Network to investigate if quantum computers could be used to optimize the settlement of large batches of financial transactions. As already noted, in 2011 aerospace giant Lockheed Martin was the first purchaser of a quantum computer manufactured by DWave Systems, and has continued to investigate use the technology for applications including air traffic management and system verification. Airbus is similarly investigating how quantum computers could speed up its research activities, and has invested in the quantum computing software company QC Ware. Meanwhile, Accenture Labs, biotech innovator Biogen and quantum software company 1QBit are researching how drug discovery could be accelerated by using quantum computiers to make molecular comparisons. Highlighting the possibilities, in September 2017, IBM used its 7 qubit hardware to simulate the structure of a threeatom beryllium hydride molecule. In October 2017, Google and Rigetti also announced OpenFermion, which is software for running chemical simulations on a quantum computer. OUR QUANTUM FUTUREAs this article has hopefully demonstrated, quantum computing is fairly rapidly morphing from fantasy to reality. Indeed, it is now reasonable to suggest that sometime in the late 2020s there will be quantum supercomputers available from the cloud that will find very practical and costeffective application. Indeed, it is perfectly possible that, ten years from now, major web search and cloud AI services will be leveraging the power of quantum computers in some of their systems, and that most users will none the wiser to this fact. Finally, for those wishing to read more, but not wishing to click on everything hyperlinked above(!), here are some selected top twelve sources for more information:
Finally (again), you can read about quantum computing  and many other and related future computing developments such as organic computing in my book Digital Genesis. 
 