This book reviews a number of spectacular advances that have been made in the study of supersymmetric quantum field theories in the last few years. Highlights include exact calculations of Wilson loop expectation values, and highly nontrivial quantitative checks of the long-standing electric-magnetic duality conjectures The book starts with an introductory article presenting a survey of recent advances, aimed at a wide audience with a background and interest in theoretical physics. The following articles are written for advanced students and researchers in quantum field theory, string theory and mathematical physics, our goal being to familiarize these readers with the forefront of current research. The topics covered include recent advances in the classification and vacuum structure of large families of N=2 supersymmetric field theories, followed by an extensive discussion of the localisation method, one of the most powerful tools for exact studies of supersymmetric field theories. The quantities that have been studied in this way are partition functions, expectation values of line operators, and supersymmetric indices. The book also reviews recently discovered connections between SUSY field theories in four dimensions and two-dimensional conformal field theory. These connections have a counterpart in relations between three-dimensional gauge theories and Chern-Simons theory; the book’s closing chapters explore connections with string theory.

Understanding the dynamics of gauge theories is crucial, given the fact that all known interactions are based on the principle of local gauge symmetry. Beyond the perturbative regime, however, this is a notoriously difficult problem. Requiring invariance under supersymmetry turns out to be a suitable tool for analyzing supersymmetric gauge theories over a larger region of the space of parameters. Supersymmetric quantum field theories in four dimensions with extended N=2 supersymmetry are further constrained and have therefore been a fertile field of research in theoretical physics for quite some time. Moreover, there are far-reaching mathematical ramifications that have led to a successful dialogue with differential and algebraic geometry. These lecture notes aim to introduce students of modern theoretical physics to the fascinating developments in the understanding of N=2 supersymmetric gauge theories in a coherent fashion. Starting with a gentle introduction to electric-magnetic duality, the author guides readers through the key milestones in the field, which include the work of Seiberg and Witten, Nekrasov, Gaiotto and many others. As an advanced graduate level text, it assumes that readers have a working knowledge of supersymmetry including the formalism of superfields, as well as of quantum field theory techniques such as regularization, renormalization and anomalies. After his graduation from the University of Tokyo, Yuji Tachikawa worked at the Institute for Advanced Study, Princeton and the Kavli Institute for Physics and Mathematics of the Universe. Presently at the Department of Physics, University of Tokyo, Tachikawa is the author of several important papers in supersymmetric quantum field theories and string theory.

This is the first systematic introduction to electromagnetic duality and its generalisations. The authors are the leading figures in this exciting new area of mathematical physics, and their lectures have been organised not only to link with each other but also to describe the fundamental ideas, the latest developments, and some earlier work whose significance has only recently become apparent. This will be essential reading for all those working in mathematical physics.

We analyze the phase structure of supersymmetric chiral gauge theories with gauge group SU(N), an antisymmetric, and F ≤ N + 3 flavors, in the presence of a cubic superpotential. When F = N + 3 the theory flows to a superconformal fixed point in the infrared, and new dual descriptions of this theory are uncovered. The theory with odd N admits a self-dual magnetic description. For general N, we find an infinite family of magnetic dual descriptions, characterized by arbitrarily large gauge groups and additional classical global symmetries that are truncated by nonperturbative effects. The infrared dynamics of these theories are analyzed using a-maximization, which supports the claim that all these theories flow to the same superconformal fixed point. A very rich phase structure is found when the number of flavors is reduced below N + 3, including a new self-dual point, transitions from conformal to confining, and a nonperturbative instability for F ≤ N. We also give examples of chiral theories with antisymmetrics that have nonchiral duals.

This volume contains the proceedings of a meeting held at Imperial College which is devoted to recent developments in string theory, supersymmetry and quantum gravity. The volume comprises two different sections. The first consists of five pedagogical reviews by prominent physicists, covering the currently important subjects of supermembranes, duality, D-branes, new non-perturbative methods and string phenomenology. The second section consists of research reports in these areas and also on other currently important topics such as supersymmetric gauge theories, two-dimensional quantum gravity and black holes.

In this thesis we use supersymmetry and the gauge-gravity duality to shed light on some dynamical features of strongly-coupled non-Abelian gauge theories. In the first half of the thesis, we consider singular superpotentials of four dimensional N=1 supersymmetric QCD and show that they must exist. In particular, using some non-trivial consistency checks, we show that these superpotentials, albeit singular, are perfectly sensible, and can be used to reproduce in a simple way both the low energy effective dynamics as well as some special higher-derivative terms. In the second half of the thesis, we investigate the behavior of timelike, spacelike and Euclidean stationary string configurations on a five-dimensional AdS black hole background which, in the context of the gauge-gravity duality, correspond to quark-antiquark pairs steadily moving in an N=4 supersymmetric Yang-Mills thermal bath. We find that there are many branches of solutions depending on the quark velocity and separation as well as on whether Euclidean or Lorentzian configurations are examined. Such solutions can, in principle, be used to determine some transport properties of strongly-coupled N=4 thermal bath.