Reversible Computing

This book describes reversible computing from the standpoint of the theory of automata and computing. It investigates how reversibility can be effectively utilized in computing. A reversible computing system is a “backward deterministic” system such that every state of the system has at most one predecessor. Although its definition is very simple, it is closely related to physical reversibility, one of the fundamental microscopic laws of Nature. Authored by the leading scientist on the subject, this book serves as a valuable reference work for anyone working in reversible computation or in automata theory in general. This work deals with various reversible computing models at several different levels, which range from the microscopic to the macroscopic, and aims to clarify how computation can be carried out efficiently and elegantly in these reversible computing models. Because the construction methods are often unique and different from those in the traditional methods, these computing models as well as the design methods provide new insights for future computing systems. Organized bottom-up, the book starts with the lowest scale of reversible logic elements and circuits made from them. This is followed by reversible Turing machines, the most basic computationally universal machines, and some other types of reversible automata such as reversible multi-head automata and reversible counter machines. The text concludes with reversible cellular automata for massively parallel spatiotemporal computation. In order to help the reader have a clear understanding of each model, the presentations of all different models follow a similar pattern: the model is given in full detail, a short informal discussion is held on the role of different elements of the model, and an example with illustrations follows each model.

Few books comprehensively cover the software and programming aspects of reversible computing. Filling this gap, Introduction to Reversible Computing offers an expanded view of the field that includes the traditional energy-motivated hardware viewpoint as well as the emerging application-motivated software approach. Collecting scattered knowledge into one coherent account, the book provides a compendium of both classical and recently developed results on reversible computing. It explores up-and-coming theories, techniques, and tools for the application of reversible computing—the logical next step in the evolution of computing systems. The book covers theory, hardware and software aspects, fundamental limits, complexity analyses, practical algorithms, compilers, efficiency improvement techniques, and application areas. The topics span several areas of computer science, including high-performance computing, parallel/distributed systems, computational theory, compilers, power-aware computing, and supercomputing. The book presents sufficient material for newcomers to easily get started. It provides citations to original articles on seminal results so that readers can consult the corresponding publications in the literature. Pointers to additional resources are included for more advanced topics. For those already familiar with a certain topic within reversible computing, the book can serve as a one-stop reference to other topics in the field.

Written by one of the few top internationally recognized experts in the field, this book concentrates on those topics that will remain fundamental, such as low power computing, reversible programming languages, and applications in thermodynamics. It describes reversible computing from various points of view: Boolean algebra, group theory, logic circuits, low-power electronics, communication, software, quantum computing. It is this multidisciplinary approach that makes it unique. Backed by numerous examples, this is useful for all levels of the scientific and academic community, from undergraduates to established academics.

This open access State-of-the-Art Survey presents the main recent scientific outcomes in the area of reversible computation, focusing on those that have emerged during COST Action IC1405 "Reversible Computation - Extending Horizons of Computing", a European research network that operated from May 2015 to April 2019. Reversible computation is a new paradigm that extends the traditional forwards-only mode of computation with the ability to execute in reverse, so that computation can run backwards as easily and naturally as forwards. It aims to deliver novel computing devices and software, and to enhance existing systems by equipping them with reversibility. There are many potential applications of reversible computation, including languages and software tools for reliable and recovery-oriented distributed systems and revolutionary reversible logic gates and circuits, but they can only be realized and have lasting effect if conceptual and firm theoretical foundations are established first.

This book constitutes the refereed proceedings of the 9th International Conference on Reversible Computation, RC 2017, held in Kolkata, India, in July 2017. The 13 full and 5 short papers included in this volume together with one invited paper were carefully reviewed and selected from 47 submissions. The papers are organized in the following topical sections: foundations; reversible circuit synthesis; reversible circuit optimization; testing and fault tolerance; and quantum circuits.

This book constitutes the refereed proceedings of the 6th International Conference on Reversible Computation, RC 2014, held in Kyoto, Japan, in July 2014. The 14 contributions presented together with three invited talks were carefully reviewed and selected from 27 submissions. The papers are organized in topical sections on automata for reversible computation; notation and languages for reversible computation; synthesis and optimization for reversible circuits; validation and representation of quantum logic.

This book constitutes the refereed proceedings of the 10th International Conference on Reversible Computation, RC 2018, held in Leicester, UK, in September 2018. The 13 full, 7 short, and one tutorial papers included in this volume together with four invited talks were carefully reviewed and selected from 28 submissions. The papers are organized in the following topical sections: reversible concurrent computation; quantum circuits; reversible programming languages; and applications.