Borel Equivalence Relations

Borel Equivalence Relations
Author: Vladimir Grigorʹevich Kanoveĭ
Publisher: American Mathematical Soc.
Total Pages: 254
Release: 2008
Genre: Mathematics
ISBN: 0821844539

"Over the last 20 years, the theory of Borel equivalence relations and related topics have been very active areas of research in set theory and have important interactions with other fields of mathematics, like ergodic theory and topological dynamics, group theory, combinatorics, functional analysis, and model theory. The book presents, for the first time in mathematical literature, all major aspects of this theory and its applications."--BOOK JACKET.

Classification and Orbit Equivalence Relations

Classification and Orbit Equivalence Relations
Author: Greg Hjorth
Publisher: American Mathematical Soc.
Total Pages: 217
Release: 2000
Genre: Mathematics
ISBN: 0821820028

Actions of Polish groups are ubiquitous in mathematics. In certain branches of ergodic theory and functional analysis, one finds a systematic study of the group of measure-preserving transformations and the unitary group. In logic, the analysis of countable models intertwines with results concerning the actions of the infinite symmetric group. This text develops the theory of Polish group actions entirely from scratch, ultimately presenting a coherent theory of the resulting orbit equivalence classes that may allow complete classification by invariants of an indicated form. The book concludes with a criterion for an orbit equivalence relation classifiable by countable structures considered up to isomorphism. This self-contained volume offers a complete treatment of this active area of current research and develops a difficult general theory classifying a class of mathematical objects up to some relevant notion of isomorphism or equivalence.

Rigidity Theorems for Actions of Product Groups and Countable Borel Equivalence Relations

Rigidity Theorems for Actions of Product Groups and Countable Borel Equivalence Relations
Author: Greg Hjorth
Publisher: American Mathematical Soc.
Total Pages: 126
Release: 2005
Genre: Mathematics
ISBN: 0821837710

Contributes to the theory of Borel equivalence relations, considered up to Borel reducibility, and measures preserving group actions considered up to orbit equivalence. This title catalogs the actions of products of the free group and obtains additional rigidity theorems and relative ergodicity results in this context.

Topics in Orbit Equivalence

Topics in Orbit Equivalence
Author: Alexander S. Kechris
Publisher: Springer Science & Business Media
Total Pages: 148
Release: 2004-08-26
Genre: Computers
ISBN: 9783540226031

This volume provides a self-contained introduction to some topics in orbit equivalence theory, a branch of ergodic theory. The first two chapters focus on hyperfiniteness and amenability. Included here are proofs of Dye's theorem that probability measure-preserving, ergodic actions of the integers are orbit equivalent and of the theorem of Connes-Feldman-Weiss identifying amenability and hyperfiniteness for non-singular equivalence relations. The presentation here is often influenced by descriptive set theory, and Borel and generic analogs of various results are discussed. The final chapter is a detailed account of Gaboriau's recent results on the theory of costs for equivalence relations and groups and its applications to proving rigidity theorems for actions of free groups.

Appalachian Set Theory

Appalachian Set Theory
Author: James Cummings
Publisher: Cambridge University Press
Total Pages: 433
Release: 2012-11-15
Genre: Mathematics
ISBN: 1139852140

This volume takes its name from a popular series of intensive mathematics workshops hosted at institutions in Appalachia and surrounding areas. At these meetings, internationally prominent set theorists give one-day lectures that focus on important new directions, methods, tools and results so that non-experts can begin to master these and incorporate them into their own research. Each chapter in this volume was written by the workshop leaders in collaboration with select student participants, and together they represent most of the meetings from the period 2006–2012. Topics covered include forcing and large cardinals, descriptive set theory, and applications of set theoretic ideas in group theory and analysis, making this volume essential reading for a wide range of researchers and graduate students.

Invariant Descriptive Set Theory

Invariant Descriptive Set Theory
Author: Su Gao
Publisher: CRC Press
Total Pages: 392
Release: 2008-09-03
Genre: Mathematics
ISBN: 9781584887942

Presents Results from a Very Active Area of ResearchExploring an active area of mathematics that studies the complexity of equivalence relations and classification problems, Invariant Descriptive Set Theory presents an introduction to the basic concepts, methods, and results of this theory. It brings together techniques from various areas of mathem

Descriptive Set Theory and Dynamical Systems

Descriptive Set Theory and Dynamical Systems
Author: M. Foreman
Publisher: Cambridge University Press
Total Pages: 304
Release: 2000-05-25
Genre: Mathematics
ISBN: 9780521786447

This volume, first published in 2000, contains a collection of survey papers providing an introduction for graduate students and researchers in these fields.

Effective Mathematics of the Uncountable

Effective Mathematics of the Uncountable
Author: Noam Greenberg
Publisher: Cambridge University Press
Total Pages: 205
Release: 2013-10-31
Genre: Mathematics
ISBN: 110751200X

Classical computable model theory is most naturally concerned with countable domains. There are, however, several methods – some old, some new – that have extended its basic concepts to uncountable structures. Unlike in the classical case, however, no single dominant approach has emerged, and different methods reveal different aspects of the computable content of uncountable mathematics. This book contains introductions to eight major approaches to computable uncountable mathematics: descriptive set theory; infinite time Turing machines; Blum-Shub-Smale computability; Sigma-definability; computability theory on admissible ordinals; E-recursion theory; local computability; and uncountable reverse mathematics. This book provides an authoritative and multifaceted introduction to this exciting new area of research that is still in its early stages. It is ideal as both an introductory text for graduate and advanced undergraduate students and a source of interesting new approaches for researchers in computability theory and related areas.