Quantum technology is approaching the mainstream. Goldman Sachs recently announced that they could introduce quantum algorithms to price financial instruments in as soon as five years. Honeywell anticipates that quantum will form a $1 trillion industry in the decades ahead. But why are firms like Goldman taking this leap — especially with commercial quantum computers being possibly years away?
To understand what’s going on, it’s useful to take a step back and examine what exactly it is that computers do.
Let’s start with today’s digital technology. At its core, the digital computer is an arithmetic machine. It made performing mathematical calculations cheap and its impact on society has been immense. Advances in both hardware and software have made possible the application of all sorts of computing to products and services. Today’s cars, dishwashers, and boilers all have some kind of computer embedded in them — and that’s before we even get to smartphones and the internet. Without computers we would never have reached the moon or put satellites in orbit.
These computers use binary signals (the famous 1s and 0s of code) that are measured in “bits” or bytes. The more complicated the code, the more processing power required and the longer the processing takes. What this means is that for all their advances — from self-driving cars to beating grandmasters at Chess and Go — there remain tasks that traditional computing devices struggle with, even when the task is dispersed across millions of machines.
A particular problem they struggle with is a category of calculation called combinatorics. These calculations involve finding an arrangement of items that optimizes some goal. As the number of items grows, the number of possible arrangements grows exponentially. To find the best arrangement, today’s digital computers basically have to iterate through each permutation to find an outcome and then identify which does best at achieving the goal. In many cases this can require an enormous number of calculations (think about breaking passwords, for example). The challenge of combinatorics calculations, as we’ll see in a minute, applies in many important fields, from finance to pharmaceuticals. It is also a critical bottleneck in the evolution of AI.
And this is where quantum computers come in. Just as classical computers reduced the cost of arithmetic, quantum presents a similar cost reduction to calculating daunting combinatoric problems.
In 2012, theoretical physicist John Preskill came up with a formulation of quantum supremacy, the superiority of quantum computers. He named it the moment when quantum computers can do things that are not possible for ordinary computers.
Seven years later, in autumn 2019, Google’s quantum computer did a calculation in less than four minutes that would take the world’s most powerful computer 10,000 years to do. It is the seed for the world’s first fully functional quantum computer that can make better medicines, create smarter artificial intelligence and solve the greatest riddles of the cosmos. Googles quantum computer Sycamore reached this milestone in 200 seconds, the machine performed a mathematically designed calculation so complex that it would take the world’s most powerful supercomputer, IBM’s Summit, 10,000 years to do it. This makes Google's quantum computer about 158 million times faster than the world’s fastest supercomputer.
The quantum computer uses the rules of quantum mechanics to perform calculations beyond human comprehension. Quantum mechanics is a branch of physics that deals with photons, electrons and atomic nuclei.
These smallest building blocks of the universe behave completely illogically. For example, the states of two particles can be connected, even though they are a long way apart, and one particle can be in two places at the same time. By mimicking the complex chemical and physical processes of nature at the atomic level, the quantum computer can help develop new medicines and invent superconducting materials that conduct electricity without loss of energy, for example.
But to start a new scientific golden age, the researchers behind the new technology still have a few hurdles to overcome.
Qubits can be everywhere at once
The computing power of the quantum computer comes from so-called quantum bits, abbreviated to qubits. On an ordinary computer, data is stored as bits with a value of 0 or 1. Four classical bits can together create 16 different data combinations — (0000, 0001, 0010, etc.) — but the classical computer can only work with one of these combinations at a time.
Qubits can have both values, 0 and 1, at the same time. In this state, called superposition, the computer can work with all 16 combinations of data at the same time. For each added qubit, computing power increases exponentially. According to the researchers, a quantum computer with 300 qubits can perform more calculations simultaneously than there are atoms in the universe.
The 0 and 1 come from the binary number system on which computers base their calculations since they were so big that they filled a living room and worked with radio tubes instead of transistors.
But for the binary numbers to work on a computer, there must be something physical that can do it. And that is the computer’s microchip: in it, millions of tiny transistors switch the current on the microchip on or off. The more transistors the microchip contains, the more information the computer can process simultaneously.
Vulnerable chip is strongly cooled
Google’s quantum computer, Sycamore, and IBM’s, IBM Q System One, also process data using microchips. Instead of millions of transistors spitting out zeros and ones, the quantum computer's brain’ contains very few qubits. The Sycamore chip has 53, and the IBM Q System One 20.
The qubits are made of the element niobium and pressed into a chip of silicon, the material that ordinary computer chips are made of.
By separating two niobium electrodes with a thin layer of aluminium oxide, a so-called Josephson contact is created, through which a quantum mechanical superposition can occur. A Josephson contact is only possible if the material is superconducting, meaning that it has no electrical resistance.
This is the biggest challenge to overcome when developing quantum computers for the home and office.
Because the properties of quantum mechanics occur only at the tiniest scale, the slightest disturbance in the calculations is enough to make them ineffective. Even one atom of air or light particle can knock the vulnerable qubits off course, causing them to lose their superposition.
That is why the quantum chip in the laboratories of both IBM and Google is located at the bottom of a freezer in a large cabinet with components made of gold and copper, which cool the chip to almost absolute zero of -273.15 ºC. This construction is called a cryostat, and it is the only thing that allows researchers to perform calculations on a quantum chip at all.
This also explains why quantum computers have not contained more qubits up to now. The more qubits they have, the harder it is to keep them in superposition for a while because of the risk of electrical interference from outside increases exponentially with the number of qubits.
Today’s quantum computers are huge and complex machines that need loads of power to cool the quantum computer chip to almost absolute zero.
Research makes a giant leap forward
Better medicines, smarter artificial intelligence and solutions of big cosmic riddles. These are just some of the scientific advances that the quantum computer may bring in the future.
1. Medical experiments are a thing of the past
Quantum computers make it possible to create, simulate and design molecular structures down to the atomic level. This allows them, for example, to simulate how a new drug will work in a human being — without first testing on humans or animals.
2. New materials see the light of day
New materials that can improve the mobile phone and the PC, and make solar cells and building materials more efficient, will emerge in the wake of the quantum computer. In particular, researchers hope that technology will provide more insight into superconducting materials, which can transport electricity without losing energy.
3. Cosmic riddles are solved
Although researchers took the world’s first picture of a black hole in 2019, we still know very little about the mysterious cosmic phenomena. The quantum computer, which can measure and analyse the smallest components of the universe, may shed new light on black holes.
4. Artificial intelligence is getting smarter
Artificial intelligence is based on so-called neural networks. These are imitations of the extensive network of nerve cells in the human brain that, just like a human being, have to be trained at first. This is a demanding process that can sometimes take weeks. With artificially intelligent quantum algorithms, the process can probably be reduced to seconds. The algorithms will therefore be able to evolve much faster and become ‘smarter’.
The next breakthrough
Despite the great advances made by Google and IBM in particular, there is still a long way to go before the extremely powerful quantum computer can be found in your home.
If you were to install a quantum computer at home, the sensitive processor would probably have to be able to operate at room temperature. Moreover, Googles quantum computer has ‘only’ beaten a supercomputer with a particularly complicated calculation designed for this purpose. The next milestone is to get a quantum computer to solve a useful problem.
To succeed in this, the quantum computer must be able to work with thousands and perhaps even millions of qubits simultaneously. And that is difficult since the structure of qubits in Google’s and IBM’s quantum computers is like a house of cards that threatens to collapse at the slightest external noise.
But perhaps a third IT giant, Microsoft, has the solution to the problem. Via a so-called topological circuit of quantum bits, this company is trying to circumvent the fragile structure of the quantum computer. The design works like Lego blocks, connecting qubits like bricks in a house and thus making the computer less vulnerable.
Whether the quantum computer will get its final breakthrough at Microsoft, Google, IBM or a fourth party is impossible to predict. One thing is certain, however: the race to get the quantum computer out of the freezing labs and prove the value of the technology has begun in earnest.
Commercial Applications of Quantum Computing
Chemical and biological engineering. Chemical and biological engineering involve the discovery and manipulation of molecules. Doing so involves the motion and interaction of subatomic particles. In other words, it involves quantum mechanics. The simulation of quantum mechanics was a key motivation in Richard Feynman's initial proposal to build a quantum computer. As molecules get more complex, the number of possible configurations grows exponentially. It becomes a combinatorics calculation, suitable for a quantum computer. For example, programmable quantum computers have already demonstrated successful simulations of simple chemical reactions, paving the way for increasingly complex chemistry simulations in the near future. With the emerging feasibility of quantum simulations, which helps predict the properties of new molecules, engineers will be able to consider molecule configurations that would otherwise be challenging to model. This ability means that quantum computers will play an important role in accelerating current efforts in materials discovery and drug development.
Cybersecurity. Combinatorics have been central to encryption for over a thousand years. Al-Khalil’s 8th century Book of Cryptographic Messages looked at permutations and combinations of words. Today’s encryption is still built on combinatorics, emphasizing the assumption that combinatoric calculations are essentially unmanageable. With quantum computing, however, cracking encryption becomes much easier, which poses a threat to data security. A new industry is growing that helps companies prepare for upcoming vulnerabilities in their cybersecurity.
As more people turn their attention to the potential of quantum computing, applications beyond quantum simulation and encryption are emerging:
Artificial intelligence. Quantum computing potentially opens up new opportunities in artificial intelligence, which often involves the combinatoric processing of very large quantities of data in order to make better predictions and decisions (think facial recognition or fraud detection). A growing research field in quantum machine learning identifies ways that quantum algorithms can enable faster AI. The current limitations on the technology and software make quantum artificial general intelligence a fairly remote possibility — but it certainly makes thinking machines more than a subject for science fiction.
Financial services. Finance was one of the earliest domains to embrace Big Data. And much of the science behind the pricing of complex assets — such as stock options — involves combinatoric calculation. When Goldman Sachs, for example, prices derivatives it applies a highly computing-intensive calculation known as a Monte Carlo simulation, which makes projections based on simulated market movements. Computing speed has long been a source of advantage in financial markets (where hedge funds vie to get millisecond advantages in obtaining price information). Quantum algorithms can increase speed for an important set of financial calculations.
Complex manufacturing. Quantum computers can be used in taking large manufacturing data sets on operational failures and translating them to combinatoric challenges that, when paired with a quantum-inspired algorithm, can identify which part of a complex manufacturing process contributed to incidents of product failure. For products like microchips where this production process can have thousands of steps, quantum can help reduce costly failures.
The opportunity for quantum computing to solve large scale combinatorics problems faster and cheaper has encouraged billions of dollars of investment in recent years. The biggest opportunity may be in finding more new applications that benefit from the solutions offered through quantum. As professor and entrepreneur Alan Aspuru-Guzik said, there is “a role for imagination, intuition, and adventure. Maybe it’s not about how many qubits we have; maybe it’s about how many hackers we have.”
Comments