Download or read book Oligomorphic Permutation Groups written by Peter J. Cameron and published by Cambridge University Press. This book was released on 1990-06-29 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of permutations groups has always been closely associated with that of highly symmetric structures. The objects considered here are countably infinite, but have only finitely many different substructures of any given finite size. This book discusses such structures, their substructures and their automorphism groups using a wide range of techniques.
Download or read book Oligomorphic Permutation Groups written by Peter Jephson Cameron and published by . This book was released on 2014-05-14 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of permutation groups has always been closely associated with that of highly symmetric structures. The objects considered here are countably infinite, but have only finitely many different substructures of any given finite size. They are precisely those structures which are determined by first-order logical axioms together with the assumption of countability. This book concerns such structures, their substructures and their automorphism groups. A wide range of techniques are used: group theory, combinatorics, Baire category and measure among them. The book arose from lectures given at a research symposium and retains their informal style, whilst including as well many recent results from a variety of sources. It concludes with exercises and unsolved research problems.
Download or read book Permutation Groups written by Peter J. Cameron and published by Cambridge University Press. This book was released on 1999-02-04 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes recent developments in the study of permutation groups for beginning graduate students.
Download or read book Notes on Infinite Permutation Groups written by Meenaxi Bhattacharjee and published by Springer Science & Business Media. This book was released on 1998-11-20 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book, based on a course of lectures by the authors at the Indian Institute of Technology, Guwahati, covers aspects of infinite permutation groups theory and some related model-theoretic constructions. There is basic background in both group theory and the necessary model theory, and the following topics are covered: transitivity and primitivity; symmetric groups and general linear groups; wreatch products; automorphism groups of various treelike objects; model-theoretic constructions for building structures with rich automorphism groups, the structure and classification of infinite primitive Jordan groups (surveyed); applications and open problems. With many examples and exercises, the book is intended primarily for a beginning graduate student in group theory.
Download or read book Classification of P oligomorphic Groups Conjectures of Cameron and Macpherson written by Justine Falque and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This PhD thesis falls under the fields of algebraic combinatorics and group theory. Precisely,it brings a contribution to the domain that studies profiles of oligomorphic permutation groups and their behaviors.The first part of this manuscript introduces most of the tools that will be needed later on, starting with elements of combinatorics and algebraic combinatorics.We define counting functions through classical examples ; with a view of studying them, we argue the relevance of adding a graded algebra structure on the counted objects.We also bring up the notions of order and lattice.Then, we provide an overview of the basic definitions and properties related to permutation groups and to invariant theory. We end this part with a description of the Pólya enumeration method, which allows to count objects under a group action.The second part is dedicated to introducing the domain this thesis comes withinthe scope of. It dwells on profiles of relational structures,and more specifically orbital profiles.If G is an infinite permutation group, its profile is the counting function which maps any n > 0 to the number of orbits of n-subsets, for the inducedaction of G on the finite subsets of elements.Cameron conjectured that the profile of G is asymptotically equivalent to a polynomial whenever it is bounded by apolynomial.Another, stronger conjecture was later made by Macpherson : it involves a certain structure of graded algebra on the orbits of subsetscreated by Cameron, the orbit algebra, and states that if the profile of G is bounded by a polynomial, then its orbit algebra is finitely generated.As a start in our study of this problem, we develop some examples and get our first hints towards a resolution by examining the block systems ofgroups with profile bounded by a polynomial -- that we call P-oligomorphic --, as well as the notion of subdirect product.The third part is the proof of a classification of P-oligomorphic groups,with Macpherson's conjecture as a corollary.First, we study the combinatorics of the lattice of block systems,which leads to identifying one special, generalized such system, that consists of blocks of blocks with good properties.We then tackle the elementary case when there is only one such block of blocks, for which we establish a classification. The proof borrows to the subdirect product concept to handle synchronizations within the group, and relied on an experimental approach on computer to first conjecture the classification.In the general case, we evidence the structure of a semi-direct product involving the minimal normal subgroup of finite index and some finite group.This allows to formalize a classification of all P-oligomorphic groups, the main result of this thesis, and to deduce the form of the orbit algebra: (little more than) an explicit algebra of invariants of a finite group. This implies the conjectures of Macpherson and Cameron, and a deep understanding of these groups.The appendix provides parts of the code that was used, and a glimpse at that resulting from the classification afterwards,that allows to manipulate P-oligomorphic groups by apropriate algorithmics. Last, we include our earlier (weaker) proof of the conjectures.
Download or read book Permutation Groups written by John D. Dixon and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following the basic ideas, standard constructions and important examples in the theory of permutation groups, the book goes on to develop the combinatorial and group theoretic structure of primitive groups leading to the proof of the pivotal ONan-Scott Theorem which links finite primitive groups with finite simple groups. Special topics covered include the Mathieu groups, multiply transitive groups, and recent work on the subgroups of the infinite symmetric groups. With its many exercises and detailed references to the current literature, this text can serve as an introduction to permutation groups in a course at the graduate or advanced undergraduate level, as well as for self-study.
Download or read book Automorphisms of First order Structures written by Richard Kaye and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection of essays discusses a range of topics linking infinite permutation group theory and model theory. Topics covered include: oligomorphic permutation groups and omega-categorical structures; totally categorical structures and covers; and Jordan groups.
Download or read book Finite Permutation Groups written by Helmut Wielandt and published by Academic Press. This book was released on 2014-05-10 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: Finite Permutation Groups provides an introduction to the basic facts of both the theory of abstract finite groups and the theory of permutation groups. This book deals with older theorems on multiply transitive groups as well as on simply transitive groups. Organized into five chapters, this book begins with an overview of the fundamental concepts of notation and Frobenius group. This text then discusses the modifications of multiple transitivity and can be used to deduce an improved form of the classical theorem. Other chapters consider the concept of simply transitive permutation groups. This book discusses as well permutation groups in the framework of representation theory. The final chapter deals with Frobenius' theory of group characters. This book is a valuable resource for engineers, mathematicians, and research workers. Graduate students and readers who are interested in finite permutation groups will also find this book useful.
Download or read book Ordered Permutation Groups written by Andrew Martin William Glass and published by Cambridge University Press. This book was released on 1981 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: As a result of the work of the nineteenth-century mathematician Arthur Cayley, algebraists and geometers have extensively studied permutation of sets. In the special case that the underlying set is linearly ordered, there is a natural subgroup to study, namely the set of permutations that preserves that order. In some senses. these are universal for automorphisms of models of theories. The purpose of this book is to make a thorough, comprehensive examination of these groups of permutations. After providing the initial background Professor Glass develops the general structure theory, emphasizing throughout the geometric and intuitive aspects of the subject. He includes many applications to infinite simple groups, ordered permutation groups and lattice-ordered groups. The streamlined approach will enable the beginning graduate student to reach the frontiers of the subject smoothly and quickly. Indeed much of the material included has never been available in book form before, so this account should also be useful as a reference work for professionals.
Download or read book Ordered Groups and Infinite Permutation Groups written by W.C. Holland and published by Springer Science & Business Media. This book was released on 2013-12-01 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: The subjects of ordered groups and of infinite permutation groups have long en joyed a symbiotic relationship. Although the two subjects come from very different sources, they have in certain ways come together, and each has derived considerable benefit from the other. My own personal contact with this interaction began in 1961. I had done Ph. D. work on sequence convergence in totally ordered groups under the direction of Paul Conrad. In the process, I had encountered "pseudo-convergent" sequences in an ordered group G, which are like Cauchy sequences, except that the differences be tween terms of large index approach not 0 but a convex subgroup G of G. If G is normal, then such sequences are conveniently described as Cauchy sequences in the quotient ordered group GIG. If G is not normal, of course GIG has no group structure, though it is still a totally ordered set. The best that can be said is that the elements of G permute GIG in an order-preserving fashion. In independent investigations around that time, both P. Conrad and P. Cohn had showed that a group admits a total right ordering if and only if the group is a group of automor phisms of a totally ordered set. (In a right ordered group, the order is required to be preserved by all right translations, unlike a (two-sided) ordered group, where both right and left translations must preserve the order.
Download or read book Notes on Infinite Permutation Groups written by Meenaxi Bhattacharjee and published by Springer. This book was released on 2006-11-14 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book, based on a course of lectures by the authors at the Indian Institute of Technology, Guwahati, covers aspects of infinite permutation groups theory and some related model-theoretic constructions. There is basic background in both group theory and the necessary model theory, and the following topics are covered: transitivity and primitivity; symmetric groups and general linear groups; wreatch products; automorphism groups of various treelike objects; model-theoretic constructions for building structures with rich automorphism groups, the structure and classification of infinite primitive Jordan groups (surveyed); applications and open problems. With many examples and exercises, the book is intended primarily for a beginning graduate student in group theory.
Download or read book Notes on Infinite Permutation Groups written by M Bhattacharjee and published by Springer. This book was released on 1997-01-01 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Permutation Groups written by Donald S. Passman and published by . This book was released on 1968 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Topics in Graph Automorphisms and Reconstruction written by Josef Lauri and published by Cambridge University Press. This book was released on 2016-06-02 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: An in-depth coverage of selected areas of graph theory focusing on symmetry properties of graphs, ideal for beginners and specialists.
Download or read book Complexity of Infinite Domain Constraint Satisfaction written by Manuel Bodirsky and published by Cambridge University Press. This book was released on 2021-06-10 with total page 537 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduces the universal-algebraic approach to classifying the computational complexity of constraint satisfaction problems.
Download or read book Handbook of Combinatorics Volume 1 written by Ronald L. Graham and published by Elsevier. This book was released on 1995-12-11 with total page 1124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Handbook of Combinatorics, Volume 1 focuses on basic methods, paradigms, results, issues, and trends across the broad spectrum of combinatorics. The selection first elaborates on the basic graph theory, connectivity and network flows, and matchings and extensions. Discussions focus on stable sets and claw free graphs, nonbipartite matching, multicommodity flows and disjoint paths, minimum cost circulations and flows, special proof techniques for paths and circuits, and Hamilton paths and circuits in digraphs. The manuscript then examines coloring, stable sets, and perfect graphs and embeddings and minors. The book takes a look at random graphs, hypergraphs, partially ordered sets, and matroids. Topics include geometric lattices, structural properties, linear extensions and correlation, dimension and posets of bounded degree, hypergraphs and set systems, stability, transversals, and matchings, and phase transition. The manuscript also reviews the combinatorial number theory, point lattices, convex polytopes and related complexes, and extremal problems in combinatorial geometry. The selection is a valuable reference for researchers interested in combinatorics.
Download or read book Graph Symmetry written by Gena Hahn and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: The last decade has seen two parallel developments, one in computer science, the other in mathematics, both dealing with the same kind of combinatorial structures: networks with strong symmetry properties or, in graph-theoretical language, vertex-transitive graphs, in particular their prototypical examples, Cayley graphs. In the design of large interconnection networks it was realised that many of the most fre quently used models for such networks are Cayley graphs of various well-known groups. This has spawned a considerable amount of activity in the study of the combinatorial properties of such graphs. A number of symposia and congresses (such as the bi-annual IWIN, starting in 1991) bear witness to the interest of the computer science community in this subject. On the mathematical side, and independently of any interest in applications, progress in group theory has made it possible to make a realistic attempt at a complete description of vertex-transitive graphs. The classification of the finite simple groups has played an important role in this respect.
