Hybrid quantum-classical systems are emerging as key platforms in quantum computing, sensing, and communication technologies, but the quantum-classical interface (QCI)-the boundary enabling these systems-introduces unique and largely unexplored security vulnerabilities. This position paper proposes using entropy-based metrics to monitor and enhance security, specifically at the QCI. We present a theoretical security outline that leverages well-established information-theoretic entropy measures, such as Shannon entropy, von Neumann entropy, and quantum relative entropy, to detect anomalous behaviors and potential breaches at the QCI. By linking entropy fluctuations to scenarios of practical relevance-including quantum key distribution, quantum sensing, and hybrid control systems-we promote the potential value and applicability of entropy-based security monitoring. While explicitly acknowledging practical limitations and theoretical assumptions, we argue that entropy-based metrics provide a complementary approach to existing security methods, inviting further empirical studies and theoretical refinements that can strengthen future quantum technologies.
Hybrid quantum-classical systems are emerging as key platforms in quantum computing, sensing, and communication technologies, but the quantum-classical interface (QCI)-the boundary enabling these systems-introduces unique and largely unexplored security vulnerabilities. This position paper proposes using entropy-based metrics to monitor and enhance security, specifically at the QCI. We present a theoretical security outline that leverages well-established information-theoretic entropy measures, such as Shannon entropy, von Neumann entropy, and quantum relative entropy, to detect anomalous behaviors and potential breaches at the QCI. By linking entropy fluctuations to scenarios of practical relevance-including quantum key distribution, quantum sensing, and hybrid control systems-we promote the potential value and applicability of entropy-based security monitoring. While explicitly acknowledging practical limitations and theoretical assumptions, we argue that entropy-based metrics provide a complementary approach to existing security methods, inviting further empirical studies and theoretical refinements that can strengthen future quantum technologies.
Quantum information, a cornerstone of modern technology, is increasingly vulnerable to attacks. Traditional cryptographic methods rely on the computational difficulty of mathematical problems, which are susceptible to noise and errors. This research introduces a novel approach leveraging quantum entropy – a fundamental property of quantum systems – to assess the security of quantum information systems. We propose a new cryptographic algorithm predicated on this entropy, demonstrating its potential to significantly enhance security through enhanced vulnerability analysis. The core mechanism involves quantifying the inherent uncertainty in a quantum system using quantum entropy, and then employing this uncertainty to build a robust, albeit probabilistic, cryptographic system. This paper outlines the theoretical framework, experimental validation, and potential applications of this approach, emphasizing its contribution to the advancement of quantum information security.
Abstract: Quantum computing and quantum information science constitute a rapidly evolving discipline at the intersection of physics, computer science, and information theory. This paper presents a systematic analysis of the conceptual foundations, theoretical frameworks, and technological challenges shaping the field. The discussion begins with the quantum-mechanical principles underpinning computation and information, followed by a rigorous framework analysis of key models such as qubits, entanglement, and quantum channels. The central problem addressed is the fragility of quantum states under noise and the corresponding need for reliable methods of computation, communication, and security. Methodologically, the paper integrates formal analysis of entropy and channel capacities with the study of error-correcting codes, fault-tolerant architectures, and emerging hardware platforms. The results synthesize advances in quantum algorithms, quantum error correction, quantum cryptography, and hybrid quantum–classical systems, highlighting both their theoretical limits and engineering realizations. The impact is evaluated through implications for secure communication, computational complexity, and future architectures, alongside ethical and societal reflections. By bridging foundational theory with practical challenges, the book offers a comprehensive resource that informs both academic inquiry and technological development. Its neutral, integrative perspective emphasizes not only the purpose of advancing reliable quantum technologies but also their broader implications for science, security, and society. Keywords Quantum computing, quantum information theory, quantum algorithms, quantum error correction, fault-tolerant quantum computation, quantum cryptography, quantum key distribution, post-quantum cryptography, entanglement, quantum channels, von Neumann entropy, quantum capacity, hybrid quantum–classical systems, quantum machine learning, quantum networks, emerging quantum architectures
The advent of quantum computing poses a significant threat to the security of currently deployed public-key cryptosystems. In response, the field of post-quantum cryptography (PQC) has emerged, proposing new algorithms based on mathematical problems believed to be hard for both classical and quantum computers. While the security of these systems is typically analyzed using computational complexity theory, this paper explores an alternative and complementary approach rooted in information theory. We investigate the security of PQC schemes by establishing entropic bounds on the information available to a quantum adversary. By leveraging concepts such as conditional min-entropy and Rényi divergence, we formulate a framework to quantify the uncertainty of secret keys and plaintexts from an adversary's perspective. This paper derives explicit entropic security bounds for several major families of post-quantum cryptosystems, including lattice-based, code-based, and hash-based schemes. We demonstrate that the security of these systems can be directly related to the entropy of the underlying hard problems' solutions. The results provide a new lens through which to assess and compare the security of PQC candidates, offering insights that are independent of specific computational models and algorithmic assumptions. This information-theoretic perspective not only strengthens the security foundations of PQC but also offers practical guidance for parameter selection to ensure long-term resilience against future cryptanalytic advances.
The advent of quantum computing poses a significant threat to the security of currently deployed public-key cryptosystems. In response, the field of post-quantum cryptography (PQC) has emerged, proposing new algorithms based on mathematical problems believed to be hard for both classical and quantum computers. While the security of these systems is typically analyzed using computational complexity theory, this paper explores an alternative and complementary approach rooted in information theory. We investigate the security of PQC schemes by establishing entropic bounds on the information available to a quantum adversary. By leveraging concepts such as conditional min-entropy and Rényi divergence, we formulate a framework to quantify the uncertainty of secret keys and plaintexts from an adversary's perspective. This paper derives explicit entropic security bounds for several major families of post-quantum cryptosystems, including lattice-based, code-based, and hash-based schemes. We demonstrate that the security of these systems can be directly related to the entropy of the underlying hard problems' solutions. The results provide a new lens through which to assess and compare the security of PQC candidates, offering insights that are independent of specific computational models and algorithmic assumptions. This information-theoretic perspective not only strengthens the security foundations of PQC but also offers practical guidance for parameter selection to ensure long-term resilience against future cryptanalytic advances.
The advent of quantum computing poses a significant threat to conventional cryptographic schemes, which rely on computational hardness assumptions vulnerable to quantum algorithms. While post-quantum cryptography (PQC) focuses on developing new computationally secure primitives, the ultimate goal of perfect secrecy, rooted in Shannon's information theory, demands a re-evaluation. This paper explores the landscape of information-theoretic security (ITS) in post-quantum regimes, moving beyond the classical Shannon limit. We review foundational concepts of ITS, including the one-time pad and its implications for perfect secrecy, and examine how quantum adversaries challenge these notions. The work delves into various approaches to achieve ITS against quantum attacks, including quantum key distribution (QKD) as a primary example, and investigates the potential for information-theoretic security from classical physical layer properties enhanced by quantum mechanics. We discuss the limitations and practical challenges of implementing such schemes, as well as the theoretical implications. This paper proposes a textit{Hybrid Information-Theoretic and Computationally Secure Architecture (HITCSA)} as a novel framework for integrating robust PQC with information-theoretically secure primitives, providing a comprehensive overview of the theoretical underpinnings and practical considerations for achieving truly secure communication in a quantum-threatened world.
Quantum entanglement, a fundamental phenomenon in quantum mechanics, offers the potential for secure communication and novel quantum technologies. This research investigates the application of quantum entanglement information entropy as a model for optimizing quantum state stability and developing a quantum key distribution (QKD) protocol. We propose a novel computational framework that leverages the unique properties of entangled states to quantify and manipulate entanglement, ultimately aiming to enhance the robustness and security of quantum systems. The core mechanism centers around quantifying the entanglement entropy, which is then used to guide parameter optimization within quantum systems. This study explores the potential of utilizing this approach to achieve improved qubit coherence and resilience against environmental noise. We present a preliminary model and outline a potential QKD protocol based on our findings.