Quantum Computing vs. Von Neumann Architecture: A New Era of Computational Power
The future of computing lies in the delicate balance between the tried-and-true and the boldly experimental.
In the 20th century, classical computers revolutionised many aspects of our lives, solving problems that would have taken lots of time. Even though computational technology has evolved to this day, there are some computational barriers that these classical computers cannot comprehend.
With the evolution of Quantum mechanics, a new form of computing, Quantum computing, is being explored. It revolutionises computational technology due to its advantages over classical computers, as it uses the principles of Quantum mechanics to perform complex computational tasks with unparalleled speed and efficiency.
Quantum computers are believed to possess the computational power to solve specific problems quickly that no classical computer could solve in any feasible amount of time, known as Quantum supremacy. In this age, most governments are racing to build a functional Quantum computer as it provides additional advantages over other nations.
The basic fundamental units involved in making the Quantum computer differ from classical computers as they depend on the Quantum behaviours of the particles rather than logical gates in modern-day classical computers.
Classical Computing & Von Neumann Architecture
Understanding Von Neumann Architecture
The basis of the Von Neumann Architecture is the Central Processing Unit (CPU). It consists of 2 parts: the Control Unit (CU) and an Arithmetic Logic Unit (ALU). CPU interacts with memory and an Input/Output (I/O) subsystem and executes a stream of Instructions (Computer Programs) that process the data stored in memory and perform I/O operations [2].
Jon Von Neumann introduced this concept in 1945, contributing to the Stored-Program Concept, which revolutionised the fundamentals and laid the foundation for modern programming systems in today’s computers.
The Legacy of Classical Computers
Classical computers, also known as modern-day computers, play a significant role today. The introduction of personal computers laid a foundation for many human needs as they developed. As for today, computers have become so close to humans that they have become inseparable.
These computers use bits (0 and 1) to store, transfer and manipulate data. A bit can be only one of two states: one or a zero. Managing data movements between the memory hierarchy optimises computational performance [1].
The new emerging technologies in processors provide adequate computational power for today’s consumers.
The Quantum Leap: Quantum Computing Fundamentals
What Makes Quantum Computing Different?
Quantum Computing is a relatively new computing paradigm that utilises Quantum principles to perform computations efficiently. As for the basic unit of information, Quantum computers use *Qubits, which play a significant part when differentiating from a Classical computer.
Defining the fundamentals of a Quantum computer brings down to three core concepts: Qubits, Superposition, and Entanglement.
Qubits
Unlike classical computers, which use bits as the basic unit of information, Quantum computers use Qubits. Although bits can achieve only two states (0 and 1), Quantum bits can achieve states between the typical o and 1, known as the *superpositions [3]. The diagram below [b] depicts a Qubit (Bloch sphere) illustration.
Superposition
Unlike classical computers, superposition is a fundamental principle in Quantum mechanics, allowing Qubits to exist simultaneously in multiple states. Therefore, Qubits can represent both 0 and 1 simultaneously.
By utilising this principle, Quantum computers achieve Quantum parallelism, enabling them to perform parallel computations and providing a significant advantage over classical computers for specific problems [5].
Entanglement
In quantum systems, entanglement is a property where two or more qubits become correlated in such a way that the state of one qubit depends on the state of the other, regardless of the distance between them.
This enables Quantum computers to perform highly interconnected computations and achieve higher computational power than conventional computers [5].
Quantum Gates
As conventional computers utilise logic gates to perform data computation, Quantum computers use Quantum gates. They are the building blocks of quantum circuits and are analogous to classical logic gates.
These gates are responsible for manipulating the state of qubits during computations. Quantum gates can perform operations such as flipping the state of a Qubit, creating superpositions, and entangling Qubits. Standard Quantum gates include the Hadamard gate, Pauli gates (X, Y, Z), and the controlled-NOT gate (CNOT) [5].
Quantum Computing Algorithms
With the utilisation of Quantum mechanics, Quantum computing has the potential to revolutionise various fields and tackle computationally infeasible problems for modern classical computers.
Utilising these fundamentals, Quantum computers can run specific algorithms that require unique properties like parallel computations. These algorithms are unique to Quantum computers because classical computers cannot perform parallel computations for exponentially complex problems [4].
An example of such an algorithm is Shor’s Algorithm, which uses the property of quantum parallelism to compute factorisation, which poses a significant threat in RSA encryption (A-Symmetric cryptography).
Quantum Computing Hardware
Although Quantum computers possess higher computational power than modern classical computers, they are in the early stages of development as they are unsuitable for an average consumer with everyday computational needs.
Quantum computers require complex hardware to function correctly. To process dynamic Quantum information, it is necessary to superconduct qubits and read the real-time states of Qubits. In contrast, classical computers are much simpler and more efficient as they work with regular logic gates and bits [6].
To function correctly, the latest Quantum computers must be stored in separate facilities at frigid temperatures (near zero Kelvin, or -273.15 Celsius). They must be handled carefully and require more than one person to operate as the old age of modern classical computers. With fast-developing technological advancements, it will become even simpler in the near future.
Conclusion
Quantum computing represents a revolutionary paradigm that can change how computations are done. Despite being in their early stages, Quantum computers show promise in new optimization methods and the ability to run complex algorithms, which are feasible to modern classical computers.
Although it has more computational capabilities than classical computers, it won’t necessarily replace them as they are entirely different computer paradigms. Still, we cannot say that Quantum computers are more efficient in performing daily human needs as classical computers have evolved and are more refined to do day-to-day tasks.
From the points given, we can compare the differences between the conventional Von Neumann computers and the Quantum computers and conclude that they are two different technologies in different computer paradigms.
References
[1] Grimes, R.A. (2019). “Introduction to Quantum Computers”.in Cryptography Apocalypse. Hoboken, NJ, USA: John Wiley & Sons, Inc, pp. 31–58. Available at: https://doi.org/10.1002/9781119618232.ch2
[2] Ogban, F., Arikpo, I., & Eteng, I. (2007). Von Neumann Architecture and Modern Computers. Global Journal of Mathematical Sciences, 6(2), 97. ISSN 1596–6208. Retrieved from http://www.ajol.info. DOI: 10.4314/gjmas.v6i2.21415
[3] Weigold, M., Barzen, J., Leymann, F., & Salm, M. (2021). Encoding patterns for quantum algorithms. IET Quantum Communication, 2. https://doi.org/10.1049/qtc2.12032
[4] Chander, S. (2023). Quantum Computers and the Emergence of Quantum Advantage.
[5] Potter, K., Mohamed, S., & Stephen, M. (2024). Quantum Computing and its Potential Applications. Computational Intelligence.
[6] Ryan, C. A., Johnson, B. R., Ristè, D., Donovan, B., & Ohki, T. A. (2017). Hardware for dynamic quantum computing. Rev. Sci. Instrum., 88(10), 104703. https://doi.org/10.1063/1.5006525
Image References:
[a]https://www.researchgate.net/publication/329842259_Looking_into_the_Black_Box _Holding_Intelligent_Agents_Accountable
[b] https://www.researchgate.net/figure/Bloch-sphere-representation-of-a-qubit_fig2_356965017
