In the last years, a considerable amount of theoretical and experimental studies have been focussing on the impact that quantum mechanics may have on computer science, information theory and cryptography. We shall loosely refer to this vast and variegated field as quantum information [64, 90, 122, 156, 183, 266, 282, 287, 359]. In the following, we shall briefly touch upon a small fraction of its many achievements.
In the last years, a considerable amount of theoretical and experimental studies have been focussing on the impact that quantum mechanics may have on computer science, information theory and cryptography. We shall loosely refer to this vast and variegated field as quantum information [64, 90, 122, 156, 183, 266, 282, 287, 359]. In the following, we shall briefly touch upon a small fraction of its many achievements.
It is now roughly thirty years since the incipient ideas on quantum information science was concretely formalized. Over the last three decades, there has been much development in this field, and at least one technology, namely devices for quantum cryptography, is now commercialized. Yet, the holy grail of a workable quantum computing machine still lies faraway at the horizon. In any case, it took nearly several centuries before the vacuum tubes were invented after the first mechanical calculating were constructed, and several decades later, for the transistor to bring the current computer technology to fruition. In this review, we provide a short survey of the current development and progress in quantum information science. It clearly does not do justice to the amount of work in the past thirty years. Nevertheless, despite the modest attempt, this review hopes to induce younger researchers into this exciting field.
Quantum Information is the science that aims to use the unusual behavior of the microscopic world, governed by the laws of Quantum Mechanics, in order to improve the way in which we compute or communicate information. Though the first ideas in this direction come from the early 80’s, it is in the last decade when Quantum Information has suffered an spectacular development. It is impossible to resume in a paper like this one the importance and complexity of the field. Therefore, I will limit to briefly explain some of the initial ideas (considered classical by now), and to briefly suggest some of the modern lines of research. By the nature of this exposition, I have decided to avoid rigor and to concentrate more in ideas and intuitions. Anyhow, I have tried to provide with enough references, in such a way that an interested reader could find there proper theorems and proofs.
The main emphasis of this work is the mathematical theory of quantum channels and their entropic and information characteristics. Quantum information theory is one of the key research areas, since it leads the way to vastly increased computing speeds by using quantum systems to store and process information. Quantum cryptography allows for secure communication of classified information. Research in the field of quantum informatics, including quantum information theory, is in progress in leading scientific centers throughout the world. The past years were marked with impressive progress made by several researchers in solution of some difficult problems, in particular, the additivity of the entropy characteristics of quantum channels. This suggests a need for a book that not only introduces the basic concepts of quantum information theory, but also presents in detail some of the latest achievements.
Quantum information theory represents a revolutionary paradigm that merges quantum mechanics with information science, fundamentally transforming our understanding of computation, communication, and information processing. This chapter provides a comprehensive examination of quantum information theory, exploring its theoretical foundations, practical applications, and transformative potential across multiple domains. We investigate the core principles including quantum bits (qubits), superposition, entanglement, and quantum interference, while analyzing their implications for quantum computing, cryptography, and communication protocols. Through systematic literature review and methodological analysis, we present current research trends, breakthrough developments, and emerging applications. The chapter addresses significant challenges including decoherence, error correction, and scalability issues that currently limit practical implementation. Our discussion encompasses quantum algorithms, quantum error correction codes, and the evolving landscape of quantum technologies. We conclude by identifying future research directions and the potential societal impact of quantum information systems, emphasizing both the unprecedented opportunities and the technical obstacles that define this rapidly advancing field.
Quantum information science is an area of study based on the idea
that information science depends on quantum effects in physics. It includes
theoretical issues in computational models as well as more experimental topics
in quantum physics including what can and cannot be done with quantum
information. Subfields include: Quantum computing, Quantum error correction,
Quantum complexity theory, Quantum cryptography and its generalization, quantum
communication, Quantum communication complexity, Quantum entanglement, Quantum
dense coding, Quantum teleportation.
In the
present book, fifteen typical literatures about Quantum Communication published
on international authoritative journals were selected to introduce the
worldwide newest progress, which contains reviews or original researches on
Communication, mechanics, optics, ect. We hope this book can demonstrate
advances in Quantum Communication as well as give references to the
researchers, students and other related people.
Information is physical. Today’s information processing and communication are classical: they are based upon the laws of Newton’s and Maxwell’s classical physics. This assertion holds all the way, from commercial computers and networks, up to their most abstract models, e.g. Turing machines. Research in quantum information was born some twenty five years ago, with the encounter of two major scientific achievements of the 20th century, namely quantum physics and information sciences. A technological motivation for that is an extrapolation of Moore’s law which seems to indicate that the amount of matter needed for one bit will be reduced to one particle sometimes before year 2020. A deeper, scientific driving force of this interdisciplinary research is that of looking for the consequences of having computation and communication based directly upon the laws of quantum physics, i.e. our current ultimate knowledge of the world of elementary particles, as described by quantum mechanics. Breakthroughs in cryptography, communications, information theory and algorithmics have shown that this transplantation from classical to quantum has far reaching consequences, both quantitative and qualitative, and opens new avenues for research within the foundations of computer science and physics. The principles 388 and most striking results and hot topics of this promising way of encoding, processing and communicating information are briefly introduced in this chapter from a mostly computer science point of view, with detailed examples in algorithmics and in cryptography. At the end of the chapter, a short list of some significant articles, textbooks and reports on quantum information are suggested for further reading.