In this small book, theoretical physicist Gerard 't Hooft (Nobel prize 1999), philosopher Emanuele Severino (Lincei Academician), and theologian Piero Coda (Pontifical Lateran University) confront one another on a topic that lies at the roots of quantum mechanics and at the origin of Western thought: Determinism and Free Will. "God does not play dice" said Einstein, a tenacious determinist. Quantum Mechanics and its clash with General Relativity have reanimated ancient dilemmas about chance and necessity: Is Nature deterministic? Is Man free? The "free-will theorem" by Conway and Kochen, and the deterministic interpretation of quantum mechanics proposed by 't Hooft, revive such philosophical questions in modern Physics. Is Becoming real? Is the Elementary Event a product of the Case? The cyclopean clash between Heraclitus and Parmenides has entered a new episode, as evidenced by the essays in this volume.

The 1996 NATO Advanced Study Institute (ASI) followed the international tradi tion of the schools held in Cargese in 1976, 1979, 1983, 1987 and 1991. Impressive progress in quantum field theory had been made since the last school in 1991. Much of it is connected with the interplay of quantum theory and the structure of space time, including canonical gravity, black holes, string theory, application of noncommutative differential geometry, and quantum symmetries. In addition there had recently been important advances in quantum field theory which exploited the electromagnetic duality in certain supersymmetric gauge theories. The school reviewed these developments. Lectures were included to explain how the "monopole equations" of Seiberg and Witten can be exploited. They were presented by E. Rabinovici, and supplemented by an extra 2 hours of lectures by A. Bilal. Both the N = 1 and N = 2 supersymmetric Yang Mills theory and resulting equivalences between field theories with different gauge group were discussed in detail. There are several roads to quantum space time and a unification of quantum theory and gravity. There is increasing evidence that canonical gravity might be a consistent theory after all when treated in. a nonperturbative fashion. H. Nicolai presented a series of introductory lectures. He dealt in detail with an integrable model which is obtained by dimensional reduction in the presence of a symmetry."

Soon after the discovery of quantum mechanics, group theoretical methods were used extensively in order to exploit rotational symmetry and classify atomic spectra. And until recently it was thought that symmetries in quantum mechanics should be groups. But it is not so. There are more general algebras, equipped with suitable structure, which admit a perfectly conventional interpretation as a symmetry of a quantum mechanical system. In any case, a "trivial representation" of the algebra is defined, and a tensor product of representations. But in contrast with groups, this tensor product needs to be neither commutative nor associative. Quantum groups are special cases, in which associativity is preserved. The exploitation of such "Quantum Symmetries" was a central theme at the Ad vanced Study Institute. Introductory lectures were presented to familiarize the participants with the al gebras which can appear as symmetries and with their properties. Some models of local field theories were discussed in detail which have some such symmetries, in par ticular conformal field theories and their perturbations. Lattice models provide many examples of quantum theories with quantum symmetries. They were also covered at the school. Finally, the symmetries which are the cause of the solubility of inte grable models are also quantum symmetries of this kind. Some such models and their nonlocal conserved currents were discussed.

The 1996 NATO Advanced Study Institute (ASI) followed the international tradi tion of the schools held in Cargese in 1976, 1979, 1983, 1987 and 1991. Impressive progress in quantum field theory had been made since the last school in 1991. Much of it is connected with the interplay of quantum theory and the structure of space time, including canonical gravity, black holes, string theory, application of noncommutative differential geometry, and quantum symmetries. In addition there had recently been important advances in quantum field theory which exploited the electromagnetic duality in certain supersymmetric gauge theories. The school reviewed these developments. Lectures were included to explain how the "monopole equations" of Seiberg and Witten can be exploited. They were presented by E. Rabinovici, and supplemented by an extra 2 hours of lectures by A. Bilal. Both the N = 1 and N = 2 supersymmetric Yang Mills theory and resulting equivalences between field theories with different gauge group were discussed in detail. There are several roads to quantum space time and a unification of quantum theory and gravity. There is increasing evidence that canonical gravity might be a consistent theory after all when treated in. a nonperturbative fashion. H. Nicolai presented a series of introductory lectures. He dealt in detail with an integrable model which is obtained by dimensional reduction in the presence of a symmetry."

With a Foreword by Steven WeinbergIn this richly illustrated book, Nobel Laureate Gerard 't Hooft and Theoretical Physicist Stefan Vandoren describe the enormous diversity of natural phenomena that take place at different time scales.In the tradition of the bestseller Powers of Ten, the authors zoom in and out in time, each step with a factor of ten. Starting from one second, time scales are enlarged until processes are reached that take much longer than the age of the universe. After the largest possible eternities, the reader is treated to the shortest and fastest phenomena known. Then the authors increase with powers of ten, until again the second is reached at the end of the book.At each time scale, interesting natural phenomena occur, spread over all scientific disciplines: orbital and rotation periods of planets and stars, decay times of elementary particles and atoms, biological rhythms and evolution processes, but also the different geological time scales. remove

UNDER THE SPELL OF THE GAUGE PRINCIPLE - by G 't HooftThe University of Bologna and its Academy of Sciences, in collaboration with the Italian National Institute for Nuclear Physics and the Italian Physical Society, celebrated in 1998 the bicentenary of a great pioneer in the field of electric phenomena - Luigi Galvani, the father of macroelectricity. During these two centuries, the physics of electric phenomena has given rise first to the Maxwell equations, then to quantum electrodynamics, and finally to the synthesis of all reproducible phenomena, the "Standard Model". A cornerstone of the Standard Model is quantum chromodynamics (QCD), which describes the interaction between quarks and gluons in the innermost part of the structure of matter.The discovery of QCD will be recalled in the future as one of the greatest achievements of mankind. Many physicists, the world over, have contributed to its creation on both the experimental and the theoretical front. Professor Antonino Zichichi has played an important role in this scientific venture, as documented by his works which are reproduced in this invaluable volume.One of the founders of European physics, Professor Victor F Weisskopf, contributes with his memories of the time when QCD had many problems. This volume owes its existence to a founding father of QCD, Professor Vladimir N Gribov, whose sudden demise prevented him from directly contributing to its final edition. Two world leaders in subnuclear theoretical physics, Professors Gerardus 't Hooft and Gabriele Veneziano, illustrate the significance of the contributions of Antonino Zichichi in QCD.

Few people studying Gauge Field Theory need to be convinced of the importance of the work of 't Hooft. This volume contains a selection of articles and review topics covering his well-known studies on the renormalization of non-Abelian gauge theorems, topological phenomena in gauge field theory and thoughts on the role of black holes in quantum gravity. The chapters are tied together by thoughtful commentaries which provide a background and the illumination of hindsight - together they form a clear and coherent picture of the physical and theoretical importance of gauge theories and the gauge principle. This book is ideal for students and researchers. Gerard 't Hooft is Professor of Theoretical Physics at the University of Utrecht, The Netherlands. He has taught at Harvard, SLAC and Caltech prior to his present position. Other distinguished honors include being awarded the Dannie Heineman Prize, the Honorary Doctorate of Science from the University of Chicago, Wolf Prize of the State of Israel, Pius XI Medal (Vatican), and the Lorentz Medal (KNAW, Amsterdam).

From 1960 until 1990 theoretical physicists and experimentalists worked together to probe deeper and deeper into the basic structure of matter, moving closer to an understanding of the ultimate building blocks of the universe. Gerard 't Hooft was closely involved in many of the advances in modern theoretical physics that led to improved understanding of elementary particles, and this is a first-hand account of one of the most creative and exciting periods of discovery in the history of physics. Using language a layperson can understand, this narrative touches on many central topics and ideas, such as quarks and quantum physics; supergravity, superstrings and superconductivity; the Standard Model and grand unification; eleven-dimensional space time and black holes. This fascinating personal account of the past thirty years in one of the most dramatic areas in twentieth-century physics will be of interest to professional physicists and physics students, as well as the educated general reader with an interest in one of the most exciting scientific detective stories ever.

From 1960 until 1990 theoretical physicists and experimentalists worked together to probe deeper and deeper into the basic structure of matter, moving closer to an understanding of the ultimate building blocks of the universe. Gerard 't Hooft was closely involved in many of the advances in modern theoretical physics that led to improved understanding of elementary particles, and this is a first-hand account of one of the most creative and exciting periods of discovery in the history of physics. Using language a layperson can understand, this narrative touches on many central topics and ideas, such as quarks and quantum physics; supergravity, superstrings and superconductivity; the Standard Model and grand unification; eleven-dimensional space time and black holes. This fascinating personal account of the past thirty years in one of the most dramatic areas in twentieth-century physics will be of interest to professional physicists and physics students, as well as the educated general reader with an interest in one of the most exciting scientific detective stories ever.

Few people studying Gauge Field Theory need to be convinced of the importance of the work of 't Hooft. This volume contains a selection of articles and review topics covering his well-known studies on the renormalization of non-Abelian gauge theorems, topological phenomena in gauge field theory and thoughts on the role of black holes in quantum gravity. The chapters are tied together by thoughtful commentaries which provide a background and the illumination of hindsight - together they form a clear and coherent picture of the physical and theoretical importance of gauge theories and the gauge principle. This book is ideal for students and researchers. Gerard 't Hooft is Professor of Theoretical Physics at the University of Utrecht, The Netherlands. He has taught at Harvard, SLAC and Caltech prior to his present position. Other distinguished honors include being awarded the Dannie Heineman Prize, the Honorary Doctorate of Science from the University of Chicago, Wolf Prize of the State of Israel, Pius XI Medal (Vatican), and the Lorentz Medal (KNAW, Amsterdam).

In this decade, the Transient Universe will be mapped out in great detail by the emerging wide-field multiwavelength surveys, and neutrino and gravitational-wave detectors, promising to probe the astronomical and physical origin of the most extreme relativistic sources. This volume introduces the physical processes relevant to the source modeling of the Transient Universe. Ideal for graduate students and researchers in astrophysics, this book gives a unified treatment of relativistic flows associated with compact objects, their dissipation and emission in electromagnetic, hadronic and gravitational radiation. After introducing the source classes, the authors set out various mechanisms for creating magnetohydodynamic outflows in winds, jets and blast waves and their radiation properties. They then go on to discuss properties of accretion flows around rotating black holes and their gravitational wave emission from wave instabilites with implications for the emerging gravitational wave experiments. Graduate students and researchers can gain an understanding of data analysis for gravitational-wave data.

This book presents the deterministic view of quantum mechanics developed by Nobel Laureate Gerard 't Hooft. Dissatisfied with the uncomfortable gaps in the way conventional quantum mechanics meshes with the classical world, 't Hooft has revived the old hidden variable ideas, but now in a much more systematic way than usual. In this, quantum mechanics is viewed as a tool rather than a theory. The author gives examples of models that are classical in essence, but can be analysed by the use of quantum techniques, and argues that even the Standard Model, together with gravitational interactions, might be viewed as a quantum mechanical approach to analysing a system that could be classical at its core. He shows how this approach, even though it is based on hidden variables, can be plausibly reconciled with Bell's theorem, and how the usual objections voiced against the idea of 'superdeterminism' can be overcome, at least in principle. This framework elegantly explains - and automatically cures - the problems of the wave function collapse and the measurement problem. Even the existence of an "arrow of time" can perhaps be explained in a more elegant way than usual. As well as reviewing the author's earlier work in the field, the book also contains many new observations and calculations. It provides stimulating reading for all physicists working on the foundations of quantum theory.