Quantum networks build on entanglement and quantum measurement to achieve tasks that are beyond the reach of classical systems. Using quantum effects, we can detect the presence of eavesdroppers, raise the sensitivity of scientific instruments such as telescopes, or teleport quantum data from one location to another. Long-distance entanglement can be used to execute important tasks such as Byzantine agreement and leader election in fewer rounds of communication than classical systems, improving the efficiency of operations that are critical in distributed systems.

This book constitutes the proceedings of the First International Conference on Quantum Communication and Quantum Networking, QuantumCom 2009, held in Naples, Italy, in October 2009. The 38 full papers were selected from numerous submissions. This conference has been devoted to the discussion of new challenges in quantum communication and quantum networking that extends from the nanoscale devices to global satellite communication networks. It placed particular emphasis on basic quantum science effects and on emerging technological solutions leading to practical applications in the communication industry, culminating with a special section on Hybrid Information Processing.

Faithful communication is a necessary precondition for large-scale quantum information processing and networking, irrespective of the physical platform. Thus, the problems of quantum-state transfer and quantum-network engineering have attracted enormous interest over the last years, and constitute one of the most active areas of research in quantum information processing. The present volume introduces the reader to fundamental concepts and various aspects of this exciting research area, including links to other related areas and problems. The implementation of state-transfer schemes and the engineering of quantum networks are discussed in the framework of various quantum optical and condensed matter systems, emphasizing the interdisciplinary character of the research area. Each chapter is a review of theoretical or experimental achievements on a particular topic, written by leading scientists in the field. The volume aims at both newcomers as well as experienced researchers.

This book provides a tutorial on quantum communication networks. The authors discuss current paradigm shifts in communication networks that are needed to add computing and storage to the simple transport ideas of prevailing networks. They show how these ‘softwarized’ solutions break new grounds to reduce latency and increase resilience. The authors discuss how even though these solutions have inherent problems due to introduced computing latency and energy consumption, the problems can be solved by hybrid classical-quantum communication networks. The book brings together quantum networking, quantum information theory, quantum computing, and quantum simulation.

This book is a historical analysis of the quantum mechanical revolution and the emergence of a new discipline from the perspective, not of a professor, but of a recent or actual Ph.D. student just embarking on an uncertain academic career in economically hard times. Quantum mechanics exploded on to the intellectual scene between 1925 and 1927, with more than 200 publications across the world, the majority of them authored by young scientists under the age of 30, graduate students or postdoctoral fellows. The resulting theory was a collective product that no single authority could claim, but it had a major geographical nod – the Copenhagen Institute of Theoretical Physics – where most of the informal, pre-published exchange of ideas occurred and where every participant of the new community aspired to visit. A rare combination of circumstances and resources – political, diplomatic, financial, and intellectual – allowed Niels Bohr to establish this “Mecca” of quantum theory outside of traditional and more powerful centres of science. Transitory international postdoctoral fellows, rather than established professors, developed a culture of research that became the source of major innovations in the field. Temporary assistantships, postdoctoral positions, and their equivalents were the chief mode of existence for young academics during the period of economic crisis and post-WWI international tensions. Insecure career trajectories and unpredictable moves through non-stable temporary positions contributed to their general outlook and interpretations of the emerging theory of quantum mechanics. This book is part of a four-volume collection addressing the beginnings of quantum physics research at the major European centres of Göttingen, Copenhagen, Berlin, and Munich; these works emerged from an expansive study on the quantum revolution as a major transformation of physical knowledge undertaken by the Max Planck Institute for the History of Science and the Fritz Haber Institute (2006–2012). For more on this project, see the dedicated Feature Story, The Networks of Early Quantum Theory, at the Max Planck Institute for the History of Science, https://www.mpiwg-berlin.mpg.de/feature-story/networks-early-quantum-theory

A highly interdisciplinary overview of the emerging topic of the Quantum Internet. Current and future quantum technologies are covered in detail, in addition to their global socio-economic impact. Written in an engaging style and accessible to graduate students in physics, engineering, computer science and mathematics.

With the fast pace of developments in quantum technologies, it is more than ever necessary to make the new generation of students in science and engineering familiar with the key ideas behind such disruptive systems. This book intends to fill such a gap between experts and non-experts in the field by providing the reader with the basic tools needed to understand the latest developments in quantum communications and its future directions. This is not only to expand the audience knowledge but also to attract new talents to this flourishing field. To that end, the book as a whole does not delve into much detail and most often suffices to provide some insight into the problem in hand. The primary users of the book will then be students in science and engineering in their final year of undergraduate studies or early years of their post-graduate programmes.