Quantum computing is gaining significant attention as one of the biggest trends in tech. Many proponents are promising its potential to revolutionize processes across industries. So, what exactly is quantum computing, and will it really be the future of tech?
Quantum computing allows for rapid processing, and complex problem solving that classical computers are not capable of, bringing developments to fields including cryptography, simulation, and optimization. In this insight, we will explain the basics of quantum computing, use cases, and its current and future place in the wider tech landscape.
What is quantum computing and how does it work?
At a basic level, the difference between classical and quantum computing is the use of bits vs qubits. Classical computers use bits as their basic unit of information – binary units which can only represent a single value, 0 or 1. Quantum computing uses qubits as its fundamental units, which can represent 0, 1, or a combination of both simultaneously.
Due to this difference, classical computers process information sequentially, while quantum computers can process many calculations simultaneously.
The nature of quantum calculations is probabilistic, meaning there are multiple possible outcomes to the same input, as opposed to the deterministic nature of calculations in classical computing, where repeating the same input will always result in the same output.
There are several key concepts to understand in quantum computing.
Superposition
Superposition refers to the ability to exist in multiple states at the same time until measured. This can be illustrated with the analogy of a coin flip – while in the air, it is representing all possible outcomes, both heads and tails, at once, and is in a state of superposition. When it lands, the outcome is determined.
In the same way, a qubit in quantum computing represents all possible values until it is measured, at which point it collapses to a single value. This principle is called superposition, and allows quantum computers to explore multiple solutions to a problem at once.
Entanglement
Entanglement is a fundamental concept in quantum mechanics, and occurs when two or more particles are related in a way that makes it impossible to describe each particle independently. This is the case even if the particles are separated by distance.
Entanglement allows quantum computers to manipulate many qubits at once and perform calculations that are not possible with classical computers. Entanglement also theoretically allows for quantum error correction. Although the methods have not yet been perfected for real-world systems, quantum computers in future should have the ability to detect and correct errors by creating and manipulating entangled states.
Quantum interference
Quantum interference is the process of particles interacting with and influencing other particles while in a state of superposition. In a quantum system, the particles exist as a probability wave of possible positions, which can interact in an interference pattern. By determining whether the waves reinforce each other (constructive interference) or cancel each other out (destructive interference), quantum interference can help guide systems towards the most likely correct solution.
Quantum computing and the cloud
Quantum computers themselves are far from accessible to businesses and researchers. The technology is still experimental, and quantum hardware is prohibitively expensive. However, with the integration of quantum computing and cloud computing, the potential accessibility of quantum technology is improving.
There are several ways quantum and cloud technologies can be integrated. Quantum workloads can be run as simulations on classical computers hosted on the cloud, which, while not giving the same capabilities as using actual quantum hardware, can be a useful tool for developing algorithms, or debugging code for example. If quantum simulation is not sufficient for the workload, processes can be executed on quantum processors hosted remotely.
A hybrid approach can also be taken, where quantum processors are used for complex, resource-intensive computations, and classical processors are used for the areas not yet able to be handled through quantum technology. The multiple elements of the hybrid infrastructure can be managed through a cloud-based interface for a seamless transition between classical and quantum computing.
It is important to note however, that at this stage, that all of these technologies and implementations are also still in their infancy.
Applications of quantum computing
While quantum computing could bring advances across industries, there are several particularly promising use-cases.
Cryptography and security
Traditional cryptography methods are based on mathematics, whereas quantum cryptography is built on the principles of quantum physics, opening up new, more secure, possibilities for security. An example is quantum key distribution (QKD), which transmits a unique key to ensure secure communication. As it is impossible to copy data encoded in a quantum state, quantum cryptography, including QKD, promises to offer near-unhackable security once practical deployment is possible.
Healthcare and medical research
Quantum computing is particularly effective at simulation, due to its ability to process vast numbers of calculations at once. The ability to speed up drug discovery and research by simulating molecules and chemical reactions could have a profound impact on the healthcare industry’s ability to cure illnesses and diseases. A recent article in the journal ‘Current Opinion in Structural Biology’ demonstrated this, concluding that ‘We will witness an exciting evolution of quantum chemistry in drug discovery’.
Logistics and optimization
With the increased calculation speed and capacity of quantum computing, it is ideal for solving complex optimization problems. For logistics and supply chain management, this could mean quantum computing being used to find optimal delivery routes for example. Research on using quantum technology for optimization is already underway – Volkswagen for example successfully conducted research into traffic-flow optimization using an algorithm on a quantum computer, stating ‘The results give us confidence for further applications on the quantum computer’.
The present and future states of quantum computing
Quantum technology has significant potential to advance computing, but it is still in the early stages. Current large-scale quantum computing projects are mostly experimental, with commercially viable systems that outperform classical computers still in development.
Some of the challenges facing a widespread adoption of quantum computing include achieving qubit stability/coherence, error rates, and the costs of the hardware. Although these challenges are substantial, many organisations are working on the solutions, and there have been significant developments in technology and funding.
A report from McKinsey noted an increase of more than 50% in public funding for quantum technologies in 2023 compared to 2022. Based on their research, they are predicting the market size for quantum computing could reach up to USD 72 billion by 2035.
It is realistic to predict that as these technological developments continue, while it is currently still in its infancy, we will start to see more elements of quantum computing used in conjunction with traditional computing and existing infrastructure. This hybrid approach of quantum and classical workloads, managed in the cloud, can bring wider accessibility and practicality to quantum technology.
