This introduction to the renormalization group, an edited and corrected second edition, discusses examples from diverse areas of physics. Designed for a one-semester course for advanced graduate students, the treatment requires a solid background in classical mechanics, statistical mechanics, and quantum mechanics. The text begins with an examination of self-similarity and scale invariance, followed by chapters on the renormalization group approaches to chaos and percolation, renormalization group and critical phenomena, and an extensive treatment of the Ising model. Additional topics include mean field theory and the Gaussian fixed point, the spherical model and the 1/n expansion, the two-dimensional X-Y model and the Kosterlitz-Thouless transition, and other subjects. Each chapter is augmented by problems and references, and three helpful Appendixes supplement the text. AUTHOR: R. J. Creswick is Professor in the Department of Physics and Astronomy, University of South Carolina.

This text fills a gap between undergraduate and more advanced texts on quantum field theory. It covers a range of renormalization methods with a clear physical interpretation, proceeds to the epsilon-expansion and ends with the first-order corrections to critical exponents beyond mean-field theory.

This is a primer on a mathematically rigorous renormalisation group theory, presenting mathematical techniques fundamental to renormalisation group analysis such as Gaussian integration, perturbative renormalisation and the stable manifold theorem. It also provides an overview of fundamental models in statistical mechanics with critical behaviour, including the Ising and φ4 models and the self-avoiding walk. The book begins with critical behaviour and its basic discussion in statistical mechanics models, and subsequently explores perturbative and non-perturbative analysis in the renormalisation group. Lastly it discusses the relation of these topics to the self-avoiding walk and supersymmetry. Including exercises in each chapter to help readers deepen their understanding, it is a valuable resource for mathematicians and mathematical physicists wanting to learn renormalisation group theory.

Originally conceived some thirty years ago in the context ofquantum electrodynamics, renormalization methods have progressivelydeveloped into an indispensable analytical tool used in widelyvarying domains of physics and applied mathematics, such as * phase transitions and critical phenomena * dynamical systems and chaos * developed turbulence * fractal structures and complex systems * percolation * polymer physics * diffusion in disordered media * measure theory and stochastic processes. By explaining the fundamental principles of renormalization theorysuch as scale invariance and universality which lie behind all thetechnical variations, this book aims to guide the reader to a moreunified understanding of today s physics. The book is based on avery accessible main text, supplemented by several more specializedsections; it is intended for graduate students and for researcherswho are seeking an introduction to a new area of electrodynamics ora general overview of the physical phenomena to whichrenormalization methods are applied.

This Brief presents an introduction to the theory of the renormalization group in the context of quantum field theories of relevance to particle physics. Emphasis is placed on gaining a physical understanding of the running of the couplings. The Wilsonian version of the renormalization group is related to conventional perturbative calculations with dimensional regularization and minimal subtraction. An introduction is given to some of the remarkable renormalization group properties of supersymmetric theories.

The main focus of this thesis is the mathematical structure of Group Field Theories (GFTs) from the point of view of renormalization theory. Such quantum field theories are found in approaches to quantum gravity related, on the one hand, to Loop Quantum Gravity (LQG) and on the other, to matrix- and tensor models. Background material on these topics, including conceptual and technical aspects, are introduced in the first chapters. The work then goes on to explain how the standard tools of Quantum Field Theory can be generalized to GFTs and exploited to study the large cut-off behaviour and renormalization group transformations of the latter. Among the new results derived in this context are a proof of renormalizability of a three-dimensional GFT with gauge group SU(2), which opens the way to applications of the formalism to quantum gravity.