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Part 1 (ISBN 978-3-7568-0801-4) of the Trilogy is based on the BoD-Book "Characterising locally finite groups satisfying the strong Sylow Theorem for the prime p - Revised edition" (see ISBN 978-3-7562-3416-5). The First edition of Part 1 (see ISBN 978-3-7543-6087-3) removes the highlights in light green of the Revised edition, adds 14 pages to the AGTA paper and 10 pages to the Revised edition. It includes Reference [11] resp. [10] as Appendix 1 resp. Appendix 2 and calls to mind Professor Otto H. Kegel's contribution to the conference Ischia Group Theory 2016. The Second edition introduces a uniform page numbering, adds page numbers to the appendices, improves 19 pages, adds Pages 109 to 112 and a Table of Contents.Part 2 (ISBN 978-3-7543-3642-8) of the Trilogy is based on the author's research paper "About the Strong Sylow Theorem for the Prime p in Simple Locally Finite Groups". We first give an overview of simple locally finite groups and reduce their Sylow theory for the prime p to a conjecture of Prof. Otto H. Kegel about the rank-unbounded ones of the 19 known families of finite simple groups. Part 2 introduces a new scheme to describe the 19 families, the family T of types, defines the rank of each type, and emphasises the rôle of Kegel covers. This part presents a unified picture of known results and is the reason why our title starts with "About". We then apply new ideas to prove the conjecture for the alternating groups (see Page ii). Thereupon we remember Kegel covers and *-sequences. Finally we suggest a plan how to prove the conjecture step-by-step which leads to further conjectures thereby unifying Sylow theory in locally finite simple groups with Sylow theory in locally finite and p-soluble groups.In Part 3 (ISBN 978-3-7578-6001-1) of the Trilogy we continue the program begun in [10] to optimise along the way 1) its Theorem about the first type "An" of infinite families of finite simple groups step-by-step to further types by proving it for the second type "A = PSLn". We start with proving the Conjecture 2 of [10] about the General Linear Groups by using new ideas (see Page ii), and then break down this insight to the Special Linear and the PSL Groups. We close with suggestions for future research regarding the remaining rank-unbounded types (the "Classical Groups") and the way 2), the (locally) finite and p-soluble groups, and Augustin-Louis Cauchy's and Évariste Galois' contributions to Sylow theory in finite groups.

This volume presents lectures given at the Wis¿a 20-21 Winter School and Workshop: Groups, Invariants, Integrals, and Mathematical Physics, organized by the Baltic Institute of Mathematics. The lectures were dedicated to differential invariants ¿ with a focus on Lie groups, pseudogroups, and their orbit spaces ¿ and Poisson structures in algebra and geometry and are included here as lecture notes comprising the first two chapters. Following this, chapters combine theoretical and applied perspectives to explore topics at the intersection of differential geometry, differential equations, and category theory. Specific topics covered include:The multisymplectic and variational nature of Monge-Ampère equations in dimension fourIntegrability of fifth-order equations admitting a Lie symmetry algebraApplications of the van Kampen theorem for groupoids to computation of homotopy types of striped surfacesA geometric framework to compare classical systemsof PDEs in the category of smooth manifoldsGroups, Invariants, Integrals, and Mathematical Physics is ideal for graduate students and researchers working in these areas. A basic understanding of differential geometry and category theory is assumed.

Self and Identity: The Basics is a jargon-free and accessible introduction that draws on key theories and ideas in Social Psychology to explore the ways that other people affect our thoughts, feelings, and behaviours.

This book is based on the author's mini course delivered at Tokyo University of Marine Science and Technology in March 2019. The shuffle approach to Drinfeld¿Jimbo quantum groups of finite type (embedding their "positive" subalgebras into q-deformed shuffle algebras) was first developed independently in the 1990s by J. Green, M. Rosso, and P. Schauenburg. Motivated by similar ideas, B. Feigin and A. Odesskii proposed a shuffle approach to elliptic quantum groups around the same time. The shuffle algebras in the present book can be viewed as trigonometric degenerations of the Feigin¿Odesskii elliptic shuffle algebras. They provide combinatorial models for the "positive" subalgebras of quantum affine algebras in their loop realizations. These algebras appeared first in that context in the work of B. Enriquez.Over the last decade, the shuffle approach has been applied to various problems in combinatorics (combinatorics of Macdonald polynomials and Dyck paths, generalization to wreath Macdonald polynomials and operators), geometric representation theory (especially the study of quantum algebras¿ actions on the equivariant K-theories of various moduli spaces such as affine Laumon spaces, Nakajima quiver varieties, nested Hilbert schemes), and mathematical physics (the Bethe ansatz, quantum Q-systems, and quantized Coulomb branches of quiver gauge theories, to name just a few).While this area is still under active investigation, the present book focuses on quantum affine/toroidal algebras of type A and their shuffle realization, which have already illustrated a broad spectrum of techniques. The basic results and structures discussed in the book are of crucial importance for studying intrinsic properties of quantum affinized algebras and are instrumental to the aforementioned applications.

The question of reconstructing a geometric shape from spectra of operators (such as the Laplace operator) is decades old and an active area of research in mathematics and mathematical physics. This book focusses on the case of compact Riemannian manifolds, and, in particular, the question whether one can find finitely many natural operators that determine whether two such manifolds are isometric (coverings).The methods outlined in the book fit into the tradition of the famous work of Sunada on the construction of isospectral, non-isometric manifolds, and thus do not focus on analytic techniques, but rather on algebraic methods: in particular, the analogy with constructions in number theory, methods from representation theory, and from algebraic topology.The main goal of the book is to present the construction of finitely many ¿twisted¿ Laplace operators whose spectrum determines covering equivalence of two Riemannian manifolds.The book has a leisure pace and presents details and examples that are hard to find in the literature, concerning: fiber products of manifolds and orbifolds, the distinction between the spectrum and the spectral zeta function for general operators, strong isospectrality, twisted Laplacians, the action of isometry groups on homology groups, monomial structures on group representations, geometric and group-theoretical realisation of coverings with wreath products as covering groups, and ¿class field theory¿ for manifolds. The book contains a wealth of worked examples and open problems. After perusing the book, the reader will have a comfortable working knowledge of the algebraic approach to isospectrality. This is an open access book.

This text presents the basic theory of random walks on infinite, finitely generated groups, along with certain background material in measure-theoretic probability. The main objective is to show how structural features of a group, such as amenability/nonamenability, affect qualitative aspects of symmetric random walks on the group, such as transience/recurrence, speed, entropy, and existence or nonexistence of nonconstant, bounded harmonic functions. The book will be suitable as a textbook for beginning graduate-level courses or independent study by graduate students and advanced undergraduate students in mathematics with a solid grounding in measure theory and a basic familiarity with the elements of group theory. The first seven chapters could also be used as the basis for a short course covering the main results regarding transience/recurrence, decay of return probabilities, and speed. The book has been organized and written so as to be accessible not only to students in probability theory, but also to students whose primary interests are in geometry, ergodic theory, or geometric group theory.

This monograph studies the heat kernel for the spin-tensor Laplacians on Lie groups and maximally symmetric spaces. It introduces many original ideas, methods, and tools developed by the author and provides a list of all known exact results in explicit form ¿ and derives them ¿ for the heat kernel on spheres and hyperbolic spaces. Part I considers the geometry of simple Lie groups and maximally symmetric spaces in detail, and Part II discusses the calculation of the heat kernel for scalar, spinor, and generic Laplacians on spheres and hyperbolic spaces in various dimensions. This text will be a valuable resource for researchers and graduate students working in various areas of mathematics ¿ such as global analysis, spectral geometry, stochastic processes, and financial mathematics ¿ as well in areas of mathematical and theoretical physics ¿ including quantum field theory, quantum gravity, string theory, and statistical physics.

This textbook provides a concise, visual introduction to Hopf algebras and their application to knot theory, most notably the construction of solutions of the Yang¿Baxter equations.Starting with a reformulation of the definition of a group in terms of structural maps as motivation for the definition of a Hopf algebra, the book introduces the related algebraic notions: algebras, coalgebras, bialgebras, convolution algebras, modules, comodules. Next, Drinfel¿d¿s quantum double construction is achieved through the important notion of the restricted (or finite) dual of a Hopf algebra, which allows one to work purely algebraically, without completions. As a result, in applications to knot theory, to any Hopf algebra with invertible antipode one can associate a universal invariant of long knots. These constructions are elucidated in detailed analyses of a few examples of Hopf algebras. The presentation of the material is mostly based on multilinear algebra, with all definitions carefully formulated and proofs self-contained. The general theory is illustrated with concrete examples, and many technicalities are handled with the help of visual aids, namely string diagrams. As a result, most of this text is accessible with minimal prerequisites and can serve as the basis of introductory courses to beginning graduate students.

This monograph thoroughly explores the development of the theory of varieties of semigroups and of two related algebras: involution semigroups and monoids. Through this in-depth analysis, readers will attain a deeper understanding of the differences between these three types of varieties, which may otherwise seem counterintuitive. New results with detailed proofs are also presented that answer previously unsolved fundamental problems. Featuring both a comprehensive overview as well as highlighting the author¿s own significant contributions to the area, this book will help establish this subfield as a matter of timely interest. Advances in the Theory of Varieties of Semigroups will appeal to researchers in universal algebra and will be particularly valuable for specialists in semigroups.

The congruences of a lattice form the congruence lattice. Over the last several decades, the study of congruence lattices has established itself as a large and important field with a great number of interesting and deep results, as well as many open problems. Written by one of the leading experts in lattice theory, this text provides a self-contained introduction to congruences of finite lattices and presents the major results of the last 90 years. It features the author¿s signature ¿Proof-by-Picture¿ method, which is used to convey the ideas behind formal proofs in a visual, more intuitive manner. Key features include:an insightful discussion of techniques to construct "nice" finite lattices with given congruence lattices and "nice" congruence-preserving extensionscomplete proofs, an extensive bibliography and index, and over 180 illustrationsadditional chapters covering new results of the lastseven years, increasing the size of this edition to 430 pages, 360 statements, and 262 referencesThis text is appropriate for a one-semester graduate course in lattice theory, and it will also serve as a valuable reference for researchers studying lattices. Reviews of previous editions:¿[This] monograph¿is an exceptional work in lattice theory, like all the contributions by this author. The way this book is written makes it extremely interesting for the specialists in the field but also for the students in lattice theory. ¿ Cosmin Pelea, Studia Universitatis Babes-Bolyai Mathematica LII (1), 2007 "The book is self-contained, with many detailed proofs presented that can be followed step-by-step. I believe that this book is a much-needed tool for any mathematician wishing a gentle introduction to the field of congruences representations of finite lattices, with emphasis on the more 'geometric' aspects." ¿ Mathematical Reviews

Effective leadership and organizational performance are concepts that continue to receive widespread attention in the business world. This book explores the importance of strategic leadership and the value it adds to organizations.

First published in 1991, this book was unique in that it not only explores the role of communication in divorce mediation, but it also presents original research to support its claims. A series of empirical studies, it points readers to a more focused set of recommendations about communication than the typical practitioner's "How-to" books.

This book examines some issues involving climate change, human trafficking, and other serious world challenges made worse by climate change. Climate change increases the risk of natural disasters and thus creates poverty and can cause situations of conflict and instability. Displacement can occur giving traffickers an opportunity to exploit affected people. In the fuzzy graph theory part of the book, the relatively new concepts of fuzzy soft semigraphs and graph structures are used to study human trafficking, as well as its time intuitionistic fuzzy sets that have been introduced to model forest fires. The notion of legal and illegal incidence strength is used to analyze immigration to the USA. The examination of return refugees to their origin countries is undertaken. The neighborhood connectivity index is determined for trafficking in various regions in the world. The cycle connectivity measure for the directed graph of the flow from South Americato the USA is calculated. It is determined that there is a need for improvement in government response by countries. Outside the area of fuzzy graph theory, a new approach to examine climate change is introduced. Social network theory is used to study feedback processes that effect climate forcing. Tipping points in climate change are considered. The relationship between terrorism and climate change is examined. Ethical issues concerning the obligation of business organizations to reduce carbon emissions are also considered. Nonstandard analysis is a possible new area that could be used by scholars of mathematics of uncertainty. A foundation is laid to aid the researcher in the understanding of nonstandard analysis. In order to accomplish this, a discussion of some basic concepts from first-order logic is presented as some concepts of mathematics of uncertainty. An application to the theory of relativity is presented.

Part 3 of the second Trilogy "The Strong Sylow Theorem for the Prime p in the Locally Finite Classical Groups" & "The Strong Sylow Theorem for the Prime p in Locally Finite and p-Soluble Groups" & "Augustin-Louis Cauchy's and Évariste Galois' Contributions to Sylow Theory in Finite Groups" proves for a subgroup G of the finite group H Lagrange's theorem and three group theorems by Cauchy, where the second and the third were concealed, by a unified method of proof consisting in smart arranging the elements of H resp. the cosets of G in H in a rectangle/tableau. Cauchy's third theorem requires the existence of a Sylow p-subgroup of H. These classical proofs are supplemented by modern proofs based on cosets resp. double cosets which take only a few lines. We then analyse first his well-known published group theorem of 1845/1846, for which he constructs a Sylow p-subgroup of Sn, thereby correcting a misunderstanding in the literature and introducing wreath products, and second his published group theorem of 1812/1815, which is related to theorems of Lagrange, Vandermonde and Ruffini. Subsequently we present what Galois knew about Cauchy's group theorems and about Sylow's theorems by referring to his published papers and as well to his posthumously published papers and to his manuscripts. We close with a detailed narrative of early group theory and early Sylow theory in finite groups.

This book consists of contributions from the participants of the Abel Symposium 2019 held in Ålesund, Norway. It was centered about applications of the ideas of symmetry and invariance, including equivalence and deformation theory of geometric structures, classification of differential invariants and invariant differential operators, integrability analysis of equations of mathematical physics, progress in parabolic geometry and mathematical aspects of general relativity.The chapters are written by leading international researchers, and consist of both survey and research articles. The book gives the reader an insight into the current research in differential geometry and Lie theory, as well as applications of these topics, in particular to general relativity and string theory.

The contents of this book was created by the authors as a simultaneous generalization of Witten zeta-functions, Mordell¿Tornheim multiple zeta-functions, and Euler¿Zagier multiple zeta-functions. Zeta-functions of root systems are defined by certain multiple series, given in terms of root systems. Therefore, they intrinsically have the action of associated Weyl groups. The exposition begins with a brief introduction to the theory of Lie algebras and root systems and then provides the definition of zeta-functions of root systems, explicit examples associated with various simple Lie algebras, meromorphic continuation and recursive analytic structure described by Dynkin diagrams, special values at integer points, functional relations, and the background given by the action of Weyl groups. In particular, an explicit form of Witten¿s volume formula is provided. It is shown that various relations among special values of Euler¿Zagier multiple zeta-functions¿which usually are called multiple zeta values (MZVs) and are quite important in connection with Zagier¿s conjecture¿are just special cases of various functional relations among zeta-functions of root systems. The authors further provide other applications to the theory of MZVs and also introduce generalizations with Dirichlet characters, and with certain congruence conditions. The book concludes with a brief description of other relevant topics.

Targeted to graduate students of mathematics, this book discusses major topics like the Lie group in the study of smooth manifolds. It is said that mathematics can be learned by solving problems and not only by just reading it. To serve this purpose, this book contains a sufficient number of examples and exercises after each section in every chapter. Some of the exercises are routine ones for the general understanding of topics. The book also contains hints to difficult exercises. Answers to all exercises are given at the end of each section. It also provides proofs of all theorems in a lucid manner. The only pre-requisites are good working knowledge of point-set topology and linear algebra.

The book is intended to serve as an introductory course in group theory geared towards second-year university students. It aims to provide them with the background needed to pursue more advanced courses in algebra and to provide a rich source of examples and exercises. Studying group theory began in the late eighteenth century and is still gaining importance due to its applications in physics, chemistry, geometry, and many fields in mathematics. The text is broadly divided into three parts. The first part establishes the prerequisite knowledge required to study group theory. This includes topics in set theory, geometry, and number theory. Each of the chapters ends with solved and unsolved exercises relating to the topic. By doing this, the authors hope to fill the gaps between all the branches in mathematics that are linked to group theory. The second part is the core of the book which discusses topics on semigroups, groups, symmetric groups, subgroups, homomorphisms, isomorphism, and Abelian groups. The last part of the book introduces SAGE, a mathematical software that is used to solve group theory problems. Here, most of the important commands in SAGE are explained, and many examples and exercises are provided.

Classification is the process of division and grouping of entities because of dissimilarities and similarities, their logical arrangement in the group and representation of each group by its unique pre-dominant characteristics. Or it is the action of classifying or categorizing or sorting of something. For example, division of living organisms into two groups viz. plant kingdom and animal kingdom because of their distinguished characteristics. It is a methodically grouping of things according to their salient features. The classified entity is a concept (an idea) or a complex of concepts, which is an acquired subjective representation of a real but not necessarily observable unit. The groups are arranged logically according to certain decided principle or standard, so that the relationships among them or inference of one group from another are clearly indicated. It is rightly said that necessity is the mother of invention. This is true in case of genesis of Universal Decimal Classification (UDC) also. When UDC was conceived, there were only DDC and Expansive classification systems in use. Dewey Decimal Classification (DDC) which had its origin in 1876 had reached its 5th ed. DDC was developed for shelf arrangement of books on the shelves. As literature was growing and becoming out of bibliographical control, two Belgians, Paul Otlet and Henri La Fontaine thought of compiling an index/bibliography at international level.

This book discusses the invertibility of fuzzy topological spaces and related topics. Certain types of fuzzy topological spaces are introduced, and interrelations between them are brought forth. Various properties of invertible fuzzy topological spaces are presented, and characterizations for completely invertible fuzzy topological spaces are discussed. The relationship between homogeneity and invertibility is examined, and, subsequently, the orbits in an invertible fuzzy topological space are studied. The structure of invertible fuzzy topological spaces is investigated, and a clear picture of the inverting pairs in an invertible fuzzy topological space is introduced. Further, the related spaces such as sums, subspaces, simple extensions, quotient spaces, and product spaces of invertible fuzzy topological spaces are examined. In addition, the effect of invertibility on fuzzy topological properties like separation axioms, axioms of countability, compactness, and fuzzy connectedness in invertible fuzzy topological spaces is established. The book sketches ideas extended to the bigger canvas of L-topology in a very interesting manner.

This book develops tools to handle C*-algebras arising as completions of convolution algebras of sections of line bundles over possibly non-Hausdorff groupoids. A fundamental result of Gelfand describes commutative C*-algebras as continuous functions on locally compact Hausdorff spaces. Kumjian, and later Renault, showed that Gelfand's result can be extended to include non-commutative C*-algebras containing a commutative C*-algebra. In their setting, the C*-algebras in question may be described as the completion of convolution algebras of functions on twisted Hausdorff groupoids with respect to a certain norm. However, there are many natural settings in which the Kumjian-Renault theory does not apply, in part because the groupoids which arise are not Hausdorff. In fact, non-Hausdorff groupoids have been a source of surprising counterexamples and technical difficulties for decades. Including numerous illustrative examples, this book extends the Kumjian-Renault theory to a much broader class of C*-algebras. This work will be of interest to researchers and graduate students in the area of groupoid C*-algebras, the interface between dynamical systems and C*-algebras, and related fields.

The book is the first full-size Encyclopedia which simultaneously covers such well-established and modern subjects as quantum field theory, supersymmetry, supergravity, M-theory, black holes and quantum gravity, noncommutative geometry, representation theory, categories and quantum groups, and their generalizations. The extraordinary historical part "e;the SUSY story,"e; more than 700 authored articles from more than 250 high-level experts (including Nobel Prize Winner Gerard 't Hooft), a detailed (50 pages) Subject/Article three level index and an Author index, make the SUSY Encyclopedia an outstanding and indispensable book on the desk of researchers, experts, Ph.D. students, specialists and professionals in modern methods of theoretical and mathematical physics.

This handbook focuses on some important topics from Number Theory and Discrete Mathematics. These include the sum of divisors function with the many old and new issues on Perfect numbers; Euler's totient and its many facets; the Mobius function along with its generalizations, extensions, and applications; the arithmetic functions related to the divisors or the digits of a number; the Stirling, Bell, Bernoulli, Euler and Eulerian numbers, with connections to various fields of pure or applied mathematics. Each chapter is a survey and can be viewed as an encyclopedia of the considered field, underlining the interconnections of Number Theory with Combinatorics, Numerical mathematics, Algebra, or Probability Theory.This reference work will be useful to specialists in number theory and discrete mathematics as well as mathematicians or scientists who need access to some of these results in other fields of research.