Quantum computing is widely promoted as a transformative technology with the potential to revolutionize fields as diverse as artificial intelligence, finance, optimization, and materials science. Yet the public narrative surrounding quantum computing often diverges sharply from the technical realities acknowledged by specialists. This paper examines the roots of this discrepancy by distinguishing the genuine scientific achievements of quantum information theory from the speculative expectations projected onto quantum hardware. After outlining the central practical challenges posed by noise, decoherence, and the extreme overhead of quantum error correction, we argue that the path to large-scale, general-purpose quantum computers remains uncertain and potentially infeasible. Drawing a historical parallel with the nuclear fusion project, we illustrate how a theoretically elegant idea may confront fundamental obstacles in physical implementation. We further analyze the sources of technological hype in both scientific and popular discourse and highlight more realistic avenues for progress, such as quantum simulation and quantum-inspired classical computation. Finally, we revisit the conceptual foundations of quantum computational advantage and emphasize that constructive probability interference - rather than superposition or entanglement alone - may provide the true insight into quantum speedups. The goal of this note is not to diminish the value of quantum information research but to restore balance between promise and feasibility, clarifying what quantum computers can and cannot achieve in practice.
Quantum computing is widely promoted as a transformative technology with the potential to revolutionize fields as diverse as artificial intelligence, finance, optimization, and materials science. Yet the public narrative surrounding quantum computing often diverges sharply from the technical realities acknowledged by specialists. This paper examines the roots of this discrepancy by distinguishing the genuine scientific achievements of quantum information theory from the speculative expectations projected onto quantum hardware. After outlining the central practical challenges posed by noise, decoherence, and the extreme overhead of quantum error correction, we argue that the path to large-scale, general-purpose quantum computers remains uncertain and potentially infeasible. Drawing a historical parallel with the nuclear fusion project, we illustrate how a theoretically elegant idea may confront fundamental obstacles in physical implementation. We further analyze the sources of technological hype in both scientific and popular discourse and highlight more realistic avenues for progress, such as quantum simulation and quantum-inspired classical computation. Finally, we revisit the conceptual foundations of quantum computational advantage and emphasize that constructive probability interference - rather than superposition or entanglement alone - may provide the true insight into quantum speedups. The goal of this note is not to diminish the value of quantum information research but to restore balance between promise and feasibility, clarifying what quantum computers can and cannot achieve in practice.
Quantum science underpins many of the most significant advances in modern physics, chemistry, and information technology. Quantum physics provides the fundamental laws governing matter and energy at microscopic scales, quantum chemistry applies these principles to explain molecular structure, bonding, and reactivity, and quantum computing seeks to exploit quantum phenomena such as superposition and entanglement to enable new computational paradigms. Despite their long-standing theoretical foundations and experimental successes, all three domains remain surrounded by persistent misconceptions, often amplified by abstract formalisms, popular science narratives, and rapid technological developments. This contemporary review critically examines the established facts and common myths associated with quantum physics, quantum chemistry, and quantum computing. Emphasis is placed on experimentally verified principles, computational feasibility, and realistic assessments of current capabilities. Recent advances reported between 2020 and 2025 are reviewed to highlight genuine progress in areas such as quantum simulations, molecular modeling, and noisy intermediate-scale quantum (NISQ) devices, while also addressing their practical limitations. By distinguishing validated achievements from speculative claims, this review provides a balanced, evidence-based perspective on modern quantum science. The article aims to clarify enduring misconceptions, promote conceptual clarity across disciplines, and outline realistic future directions for research and applications in quantum technologies.
Quantum computing represents a transformative paradigm that exploits the principles of quantum mechanics—superposition, entanglement, and quantum interference—to perform computations beyond the capabilities of classical computers. This review presents a comprehensive overview of the fundamental concepts underlying quantum computation, including qubits, quantum gates, quantum algorithms and measurement theory. It further examines major physical implementations of quantum computers, such as superconducting circuits, trapped ions, photonic systems, spin-based qubits, and topological approaches, highlighting their operational principles, advantages, and technological limitations. Key challenges hindering large-scale quantum computation—decoherence, error rates, qubit scalability, and fault tolerance—are critically discussed. Additionally, recent progress in quantum error correction, hybrid quantum–classical algorithms, and hardware optimization is summarized. The review concludes by outlining future research directions and potential applications of quantum computing in cryptography, materials science, optimization, and drug discovery. By integrating theoretical foundations with experimental advancements, this article aims to provide a clear and accessible reference for students, researchers, and scientists entering the rapidly evolving field of quantum computing.
Quantum computing leverages quantum mechanical concepts, including superposition, entanglement, and interference, to solve problems that traditional computers cannot handle efficiently. This study presents a comprehensive overview of the field, covering both the theoretical foundations and the latest developments in quantum hardware and algorithms. This study covers fundamental elements, qubits, gates, and circuits while emphasizing quantum parallelism as a distinctive feature. To illustrate efficiency gains, we explore notable algorithms like Shor’s factorization procedure and Grover’s search algorithm. Furthermore, we analyze recent advancements in quantum hardware, focusing on superconducting qubits, trapped ions, and photonic quantum computers, with an emphasis on implementations by IBM, Google, and other industry leaders. The discussion also addresses major challenges such as decoherence, noise, and the need for quantum error correction to achieve fault tolerance. Finally, we explore emerging applications in cryptography, optimization, quantum machine learning, and material simulation, and identify critical open problems that must be addressed to realize scalable, universal quantum computing. Our review underscores the transformative potential of quantum technologies across science and industry.
This article provides a comprehensive technical examination of quantum computing systems based on qubit technology, exploring their revolutionary potential to transform computational capabilities beyond classical limitations. Beginning with an analysis of the fundamental quantum mechanical principles—superposition, entanglement, and quantum interference—the article elucidates how these phenomena enable exponential computational advantages for specific problem domains. Various physical implementations of qubits are evaluated, including superconducting circuits, trapped ions, photonic systems, and theoretical topological approaches, with each platform presenting unique advantages and engineering challenges. It extends to practical applications across cryptography, optimization, and artificial intelligence, where quantum computing promises transformative capabilities. However, significant obstacles remain, including decoherence, high error rates, scalability limitations, and the ongoing development of practical quantum algorithms. Despite these challenges, the quantum computing landscape is evolving toward a hybrid paradigm where quantum and classical resources work in concert, with specialized quantum processors likely to deliver commercial value in specific domains before universal quantum computers become a reality.
Quantum computing has emerged as a transformative computational paradigm capable of addressing limitations increasingly encountered by classical computing systems as Moore’s law approaches physical and economic constraints. By leveraging quantum mechanical principles such as superposition, entanglement, and interference, quantum systems offer the potential for significant computational advantages in solving complex problems that are currently infeasible for conventional architectures. This review critically synthesizes recent advances in quantum computing by examining foundational principles, major algorithmic breakthroughs, evolving hardware platforms, and interdisciplinary real-world applications. A structured narrative literature review was conducted using major scientific databases, including PubMed, IEEE Xplore, Nature, ScienceDirect, and arXiv, with emphasis on peer-reviewed studies, landmark foundational research, and major industry developments published between 2018 and 2026. Key findings indicate substantial progress in superconducting, trapped ion, photonic, and topological quantum systems, alongside innovations in algorithms such as Shor’s, Grover’s, variational quantum methods, and quantum machine learning. Despite these advancements, major challenges including decoherence, noise, scalability limitations, and fault-tolerant error correction remain substantial barriers to commercial maturity. Future implications suggest quantum computing may profoundly influence artificial intelligence, cybersecurity, optimization, molecular simulation, and scientific discovery, particularly through hybrid classical-quantum systems and cloud-based democratization. Although practical deployment remains transitional, quantum computing is positioned to become a foundational technology with broad scientific, industrial, and societal implications.
Quantum computing is widely portrayed as a revolutionary technological paradigm, promising exponential speedups and unprecedented computational capabilities through the manipulation of quantum superposition, entanglementandinterference. This paper presents a com-prehensive and interdisciplinary refutation of such claims, demonstrating that the prevailing narrative is mathematically incoherent, physically implausible, economically irrationalandpolitically constructed. Beginning with a rigorous critique of the misinterpretation of quantum states as parallel classical processes, we show that superposition and entanglement do not provide the kind of computational multiplicity often claimed. We examine the hard limits imposed by decoherence, errorcorrectionoverheadandthermodynamic constraints, revealing that scalable, fault-tolerant quantum computation remains physically infeasible under any realistic engineering regime. We further demonstrate that quantum computing introduces no newclass of computable functions and remains firmly within the boundaries of the Church–Turing thesis. Economically, we analyse the high costs and narrow applicability of proposed quantum advantages, concluding that even where theoretical speedups exist, the resource overhead renders them impractical. Finally, we dissect the political economy of quantum computing as a form of security theatre, wherein opaque scientific discourse is exploited to secure funding, generate institutional rentsandsustain a techno-political myth. This paper reasserts the necessity of epistemic rigour, economic rationalityandphysical realism in evaluating emerging technologiesandargues that the current trajectory of quantum computing investment constitutes a paradigmatic case of institutionalised overpromise.