From the reviews: "Serre's notes on groups acting on trees have appeared in various forms (all in French) over the past ten years and they have had a profound influence on the development of many areas, for example, the theory of ends of discrete groups. This fine translation is very welcome and I strongly recommend it as an introduction to an important subject. In Chapter I, which is self-contained, the pace is fairly gentle. The author proves the fundamental theorem for the special cases of free groups and tree products before dealing with the (rather difficult) proof of the general case."(A.W. Mason in Proceedings of the Edinburgh Mathematical Society 1982)

Symmetry and Economic Invariance: An Introduction explores how symmetry and invariance of economic models can provide insights into their properties. While the professional economist is nowadays adept at many of the mathematical techniques used in static and dynamic optimization models, group theory is still not among his or her repertoire of tools. The authors aim to show that group theoretic methods form a natural extension of the techniques commonly used in economics and that they can be easily mastered.

An encompassing socio-historical survey of the political and sociological nature of groups, communities and societies. A transdisciplinary study of crowds, masses and groups as historical, sociological, psychological and psychosocial phenomena. A unique combination of sociology, psychoanalysis and group analysis in the study of social formations. An inquiry into the enigma of crowds and mass psychology with the history of group analytic and group relations' advances in England, especially the study of large groups in the research on group processes. A comprehensive presentation of the social unconscious theory in association with the study of large groups and the Incohesion theory as new group analytic tools for understanding contemporary crowds and masses. In today's world, flooded by social conflicts and polarizations and the mass impact of social media, this book enables the reader to map out the field of the unconscious life of crowds illuminating the darkness of twenty-first century collective movements.

The topic of this book is finite group actions and their use in order to approach finite unlabeled structures by defining them as orbits of finite groups of sets. Well-known examples are graph, linear codes, chemical isomers, spin configurations, isomorphism classes of combinatorial designs etc.The second edition is an extended version and puts more emphasis on applications to the constructive theory of finite structures. Recent progress in this field, in particular in design and coding theory, is described.This book will be of great use to researchers and graduate students.

This book attempts to 'shake up' the current complacency around therapy and 'mental health' behaviours by putting therapy fully into context using Social Contextual Analysis; showing how changes to our social, discursive, and societal environments, rather than changes to an individual's 'mind', will reduce suffering from the 'mental health' behaviours. Guerin challenges many assumptions about both current therapy and psychology, and offers alternative approaches, synthesized from sociology, social anthropology, sociolinguistics, and elsewhere. The book provides a way of addressing the 'mental health' behaviours including actions, talking, thinking, and emotions, by taking people's external life situations into account, and not relying on an imagined 'internal source'. Guerin describes the broad contexts for current Western therapies, referring to social, discursive, cultural, societal, and economic contexts, and suggests that we need to research the components of therapies and stop treating therapies as units. He reframes different types of therapy away from their abstract jargons, offering an alternative approach grounded in our real social worlds, aligning with new thinking that challenges the traditional methods of therapy, and also providing a better framework for rethinking psychology itself. The book ultimately suggests more emphasis should be put on 'mental health' behaviours as arising from social issues including the modern contexts of extreme capitalism, excessive bureaucracy, weakened discursive communities, and changing forms of social relationships. Practical guidelines are provided for building the reimagined therapies into clinics and institutions where labelling and pathologizing the 'mental health' behaviours will no longer be needed. By putting 'mental health' behaviours and therapy into a naturalistic or ecological social sciences framework, this book will be practical and fascinating reading for professional therapists, counsellors, social workers, and mental health nurses, as well as academics interested in psychology and the social sciences more generally.

Thisseries is devoted to the publication of monographs, lecture resp. seminar notes, and other materials arising from programs of the OSU Mathemaical Research Institute. This includes proceedings of conferences or workshops held at the Institute, and other mathematical writings.

Routledge Library Editions: The City reprints some of the most important works in urban studies published in the last century. For further information on this collection please email [email protected].

City, Region and Regionalism was first published in 1947.

Do large cities grow more or less rapidly than small ones? Why should the relationship between city size and population growth vary so much from one period to another? This book studies the process of population growth in a national set of cities, relating its findings to the theoretical concepts of urban geography. To test his ideas, the author studies the growth of cities in England and Wales between 1801 and 1911. His explanations draw strongly on the connection between growth and the adoption of innovations. He develops a model of innovation diffusions in a set of cities and, in support of this model, looks at the way in which three particular innovations - the telephone, building societies and gaslighting - spread amongst English towns in the nineteenth century. This book was first published in 1973.

Hall argues that 'London was the chief manufacturing centre of the country in 1861, and without doubt for centuries before that'. This book looks at industries in London over time from 1861. This book was first published in 1962.

This book was first published in 1970.

The aim of this text is to provide a concise treatment of some topics from group theory and representation theory for a one term course. It focuses on the non-commutative side of the field emphasizing the general linear group as the most important group and example. The book should enable graduate students from every mathematical field, as well as strong undergraduates with an interest in algebra, to solidify their knowledge of group theory. The reader should have a familiarity with groups, rings and fields, along with a solid knowledge of linear algebra. Close to 200 exercises of varying difficulty serve both to reinforce the main concept of the text and to expose the reader to additional topics.

This second volume deals with the relative homological algebra of complexes of modules and their applications. It is a concrete and easy introduction to the kind of homological algebra which has been developed in the last 50 years. The book serves as a bridge between the traditional texts on homological algebra and more advanced topics such as triangulated and derived categories or model category structures. It addresses to readers who have had a course in classical homological algebra, as well as to researchers.

This book is a study in economic geography, treated historically. Its primary purpose is to describe and explain the industrial geography of London since 1861, using the most recent statistics available for that purpose, noting that this work was originally published in 1962.

This proceedings volume, the fifth in a series from the Combinatorial and Additive Number Theory (CANT) conferences, is based on talks from the 19th annual workshop, held online due to the COVID-19 pandemic. Organized every year since 2003 by the New York Number Theory Seminar at the CUNY Graduate Center, the workshops survey state-of-the-art open problems in combinatorial and additive number theory and related parts of mathematics. The CANT 2021 meeting featured over a hundred speakers from North and South America, Europe, Asia, Australia, and New Zealand, and was the largest CANT conference in terms of the number of both lectures and participants. These proceedings contain peer-reviewed and edited papers on current topics in number theory. Topics featured in this volume include sumsets, minimal bases, Sidon sets, analytic and prime number theory, combinatorial and discrete geometry, numerical semigroups, and a survey of expansion, divisibility, and parity. This selection of articles will be of relevance to both researchers and graduate students interested in current progress in number theory.

This volume presents the core of invited expository lectures given at the 1993 NATO ASI held at the University of York. The subject matter of the ASI was the interplay between automata, semigroups, formal languages and groups. The invited talks were of an introductory nature but at a high level and many reached the cutting edge of research in the area. The lectures were given to a mixed group of students and specialists and were designed to be accessible to a broad audience. The papers were written in a similar spirit in the hope that their readership will be as wide as possible. With one exception they are all based on the talks which the lecturers gave at the meeting. The exception is caused by the fact that due to unanticipated progress the topic of John Rhodes' talk is now in such a state of flux that it has not been possible to produce a paper giving a clear picture of the situation. However, we do include an article by a member of the "Rhodes school" , namely Christopher Nehaniv, expanding on a contributed talk he gave. It generalizes the celebrated Krohn-Rhodes theorem for finite semigroups to all semigroups. For many years there has been a strong link between formal language theory and the theory of semigroups. Each subject continues to influence the other.

This book presents the relationship between ultrafilters and topologies on groups. It shows how ultrafilters are used in constructing topologies on groups with extremal properties and how topologies on groups serve in deriving algebraic results about ultrafilters. The contents of the book fall naturally into three parts. The first, comprising Chapters 1 through 5, introduces to topological groups and ultrafilters insofar as the semigroup operation on ultrafilters is not required. Constructions of some important topological groups are given. In particular, that of an extremally disconnected topological group based on a Ramsey ultrafilter. Also one shows that every infinite group admits a nondiscrete zero-dimensional topology in which all translations and the inversion are continuous. In the second part, Chapters 6 through 9, the Stone-Cech compactification G of a discrete group G is studied. For this, a special technique based on the concepts of a local left group and a local homomorphism is developed. One proves that if G is a countable torsion free group, then G contains no nontrivial finite groups. Also the ideal structure of G is investigated. In particular, one shows that for every infinite Abelian group G, G contains 22|G| minimal right ideals. In the third part, using the semigroup G, almost maximal topological and left topological groups are constructed and their ultrafilter semigroups are examined. Projectives in the category of finite semigroups are characterized. Also one shows that every infinite Abelian group with finitely many elements of order 2 is absolutely -resolvable, and consequently, can be partitioned into subsets such that every coset modulo infinite subgroup meets each subset of the partition. The book concludes with a list of open problems in the field. Some familiarity with set theory, algebra and topology is presupposed. But in general, the book is almost self-contained. It is aimed at graduate students and researchers working in topological algebra and adjacent areas.

The modern theory of Kleinian groups starts with the work of Lars Ahlfors and Lipman Bers; specifically with Ahlfors' finiteness theorem, and Bers' observation that their joint work on the Beltrami equation has deep implications for the theory of Kleinian groups and their deformations. From the point of view of uniformizations of Riemann surfaces, Bers' observation has the consequence that the question of understanding the different uniformizations of a finite Riemann surface poses a purely topological problem; it is independent of the conformal structure on the surface. The last two chapters here give a topological description of the set of all (geometrically finite) uniformizations of finite Riemann surfaces. We carefully skirt Ahlfors' finiteness theorem. For groups which uniformize a finite Riemann surface; that is, groups with an invariant component, one can either start with the assumption that the group is finitely generated, and then use the finiteness theorem to conclude that the group represents only finitely many finite Riemann surfaces, or, as we do here, one can start with the assumption that, in the invariant component, the group represents a finite Riemann surface, and then, using essentially topological techniques, reach the same conclusion. More recently, Bill Thurston wrought a revolution in the field by showing that one could analyze Kleinian groups using 3-dimensional hyperbolic geome try, and there is now an active school of research using these methods."

This is the second revised edition of an introduction to contemporary relative homological algebra. It supplies important material essential to understand topics in algebra, algebraic geometry and algebraic topology. Each section comes with exercises providing practice problems for students as well as additional important results for specialists. In this new edition the authors have added well-known additional material in the first three chapters, and added new material that was not available at the time the original edition was published. In particular, the major changes are the following: Chapter 1: Section 1.2 has been rewritten to clarify basic notions for the beginner, and this has necessitated a new Section 1.3. Chapter 3: The classic work of D. G. Northcott on injective envelopes and inverse polynomials is finally included. This provides additional examples for the reader. Chapter 11: Section 11.9 on Kaplansky classes makes volume one more up to date. The material in this section was not available at the time the first edition was published. The authors also have clarified some text throughout the book and updated the bibliography by adding new references. The book is also suitable for an introductory course in commutative and ordinary homological algebra.

A series of three symposia took place on the topic of trace formulas, each with an accompanying proceedings volume. The present volume is the third and final in this series and focuses on relative trace formulas in relation to special values of L-functions, integral representations, arithmetic cycles, theta correspondence and branching laws. The first volume focused on Arthur's trace formula, and the second volume focused on methods from algebraic geometry and representation theory. The three proceedings volumes have provided a snapshot of some of the current research, in the hope of stimulating further research on these topics. The collegial format of the symposia allowed a homogeneous set of experts to isolate key difficulties going forward and to collectively assess the feasibility of diverse approaches.

This updated edition of this classic book is devoted to ordinary representation theory and is addressed to finite group theorists intending to study and apply character theory. It contains many exercises and examples, and the list of problems contains a number of open questions.

The first contribution by Carter covers the theory of finite groups of Lie type, an important field of current mathematical research. In the second part, Platonov and Yanchevskii survey the structure of finite-dimensional division algebras, including an account of reduced K-theory.

It was already in 1964 Fis66] when B. Fischer raised the question: Which finite groups can be generated by a conjugacy class D of involutions, the product of any two of which has order 1, 2 or 37 Such a class D he called a class of 3-tmnspositions of G. This question is quite natural, since the class of transpositions of a symmetric group possesses this property. Namely the order of the product (ij)(kl) is 1, 2 or 3 according as {i, j} n {k, l} consists of 2,0 or 1 element. In fact, if I{i, j} n {k, I}1 = 1 and j = k, then (ij)(kl) is the 3-cycle (ijl). After the preliminary papers Fis66] and Fis64] he succeeded in Fis71J, Fis69] to classify all finite "nearly" simple groups generated by such a class of 3-transpositions, thereby discovering three new finite simple groups called M(22), M(23) and M(24). But even more important than his classification theorem was the fact that he originated a new method in the study of finite groups, which is called "internal geometric analysis" by D. Gorenstein in his book: Finite Simple Groups, an Introduction to their Classification. In fact D. Gorenstein writes that this method can be regarded as second in importance for the classification of finite simple groups only to the local group-theoretic analysis created by J. Thomp

The aim of the Expositions is to present new and important developments in pure and applied mathematics. Well established in the community over more than two decades, the series offers a large library of mathematical works, including several important classics. The volumes supply thorough and detailed expositions of the methods and ideas essential to the topics in question. In addition, they convey their relationships to other parts of mathematics. The series is addressed to advanced readers interested in a thorough study of the subject. Editorial Board Lev Birbrair, Universidade Federal do Ceara, Fortaleza, Brasil Walter D. Neumann, Columbia University, New York, USA Markus J. Pflaum, University of Colorado, Boulder, USA Dierk Schleicher, Jacobs University, Bremen, Germany Katrin Wendland, University of Freiburg, Germany Honorary Editor Victor P. Maslov, Russian Academy of Sciences, Moscow, Russia Titles in planning include Yuri A. Bahturin, Identical Relations in Lie Algebras (2019) Yakov G. Berkovich, Lev G. Kazarin, and Emmanuel M. Zhmud', Characters of Finite Groups, Volume 2 (2019) Jorge Herbert Soares de Lira, Variational Problems for Hypersurfaces in Riemannian Manifolds (2019) Volker Mayer, Mariusz Urbanski, and Anna Zdunik, Random and Conformal Dynamical Systems (2021) Ioannis Diamantis, Bostjan Gabrovsek, Sofia Lambropoulou, and Maciej Mroczkowski, Knot Theory of Lens Spaces (2021)

This book presents a collection of carefully refereed research articles and lecture notes stemming from the Conference "Automorphic Forms and L-Functions", held at the University of Heidelberg in 2016. The theory of automorphic forms and their associated L-functions is one of the central research areas in modern number theory, linking number theory, arithmetic geometry, representation theory, and complex analysis in many profound ways. The 19 papers cover a wide range of topics within the scope of the conference, including automorphic L-functions and their special values, p-adic modular forms, Eisenstein series, Borcherds products, automorphic periods, and many more.