The obvious answer to this question is further developments in AI. The creation of an AI that is almost indistinguishable from humanity, a thinking, feeling robot. Such a development would revolutionize the world, raise philosophical questions about what it means to be human and start a radical change in the definition of human rights. Even whilst entering this essay reminders have been presented about the importance of writing original work and not exploiting new AI technologies like Chat GPT. You can be forgiven for assuming this is the correct answer to the question present. Yet this invention will not shake the world like the success in developing a working quantum computer will.
Quantum computing has the potential to change the field of computer science as we know it and will have considerable influence on the fields of medical research, weather modelling, EV battery development, cyber security and chemistry among many others. Looking at quantum computing more closely, it almost seems disappointing; realistically the common man will never see a quantum computer and it’s highly unlikely it will ever be integrated into the new smartphone. Instead, hidden away, the new quantum supercomputer can radically change society. How? Through pure computational power.
A quantum computer relies on the theory of quantum mechanics. A field so complex that it inspired the quote (by Richard Feynman): “It’s safe to say that nobody understands quantum mechanics”. Specifically, quantum computing is dependent on the theory of superposition. The idea is that an object can be in two states at one time and is by extension in both states at one time. The concept is best demonstrated in Erwin Schrödinger’s famous thought experiment. The thought experiment, originally conceived in 1935, involves a cat placed in a box with a radioactive isotope connected to a vial of poison. The cat is left alone in the box for an hour, within this time it has a 50% chance of being killed and a 50% chance of surviving. Until the box is opened it can be assumed that the cat is both alive and dead. This superposition of states, the cat being both alive and dead, is also seen in the real world, perhaps most famously in electron diffraction, in which an electron exhibits wavelike properties and passes through multiple slits at once.
A classic or regular computer is made up of transistors or bits which represent 1s or 0s. However, in a quantum computer, each bit is both a 1 and a 0. These superposed bits are known as qubits. If a quantum computer contained 8 bits, it could represent all 256 possible numbers at once. Theoretically, a great number of calculations could be performed simultaneously improving computational power immensely. However, with the development of such computers, two fundamental flaws have appeared. Both rely on the fact that superposition can only occur unobserved, the cat is only dead and alive whilst the box is sealed. Firstly, any output of a calculation, once observed settles into a random result, so whilst the calculation performed may include all 256 possible numbers (for 8 qubits) the observed output will only produce one. This is mitigated by including phase, which is used to cancel out some superposition states to result in only useful answers.
The second flaw is the concept of noise. Superposition is extremely fragile, things as small as a cosmic ray can jeopardise the superposition state. As the qubits are worked on, they are exposed to the outside world and risk falling out of their superposed state, this would result in a quantum computer being reduced to an extremely expensive classical computer. As a result, noise cancellation is required to make a quantum computer effective. This requires millions of qubits to even begin to be able to run programs. As of 24th October 2023, the largest number of qubits in a supercomputer was 1180, held by Atom Computing (Wilkins, 2023), nowhere near the millions required to utilise a quantum computer’s full potential.
The development of a working quantum computer is now a race between corporations, without a standard method of creating a qubit, corporations are each developing various strategies to create the most effective solution possible. Oxford University and Atom Computing are both investigating trapped ions which relies on lasers to maintain the superposition state. Google and IBM are researching superconducting qubits, which use the properties of superconducts and low temperatures to maintain superposition. Finally, photon qubits are being explored by PsiQuantum. Photon qubits use trenches etched into silicon when these trenches pass close to one another they “leak” into one another and result in a superposition.
But once a dominant type of qubit has been established, what are the implications for the wider world? Earlier in the essay, the implications of quantum computing for medicine were mentioned. With the ability to perform complex mathematics faster than ever before, quantum computers will be able to synthesise interactions between possible drugs, pathogens, and human cells. And will result in a boom in drug development in the medical world.
Another field in which quantum computing could radicalise is the field of cyber security; at present the most secure form of cyber security is RSA encryption and with a complex enough key, the encryption is uncrackable with a classic computer. The private key is two prime numbers with the public key being the product of these two numbers. According to the book “The Code Book” (Singh, 1999, p. 227) a private key greater than 10308 would take over a thousand years to crack assuming all personal computers were put together to work on the project. Prime factorisation, the backbone of RSA encryption, is (currently) an NP problem, meaning it can be completed but may require an exponential number of steps. However, with quantum computing, an algorithm has already been written to calculate prime factors of extremely large numbers, rendering RSA encryption redundant and leaving substantial weakness within encryption systems worldwide. Despite this, quantum theory, the concepts at the heart of a quantum computer, also provide an opportunity for potentially uncrackable encryption.
As with any computational development, there is the potential for advancements in machine learning and neural networks (two branches of AI). Despite this possibility, it is highly unlikely that machine learning or neural networks will be the focus of quantum computing for a while yet as this is reliant upon a Q-RAM which is a long way off. In the time taken for a Q-RAM to be developed, quantum computing will have already made a substantial difference to other areas and those initial developments in such a wide range of disciplines are arguably more significant legacy than that of the quantum computer’s inevitable development in AI.
In conclusion, whilst quantum computing is still a way off, it has significant influence over a substantial number of fields and will radicalise the world of computing. Although you may never see one, the ripples of its effect will impact all human life. Despite the hyper-fixation on the development of AI at present, it will ultimately be quantum computing that is the next greatest advancement in computer science engineering.
