Texts and Monographs in Physics Series Editors: R. Balian, Gif-sur-Yvette, France W. Bei9lb6ck, Heidelberg, Germany t, H. Grosse,Wien,Austria E.H. Lieb, Princeton, NJ, USA N. Reshetikhin, Berkeley, CA, USA H. Spohn, Minchen, Germany W. Thirring,Wien,Austria Springer Berlin Heidelberg NewYork HongKong F London - ONLINELIBRARY Milan Physics andAstronomy H, Paris Tokyo http://www.springerde/phys/ 01a Bratteli Derek W. Robinson Operator Algebras d Q uantum an StatisticaIM hanic I ec s C*- and W*-Algebras Symmetry Groups Decomposition of States Second Edition 4 Springer ProfessorOlaBratteli UniversitetetiOslo MatematiskInstitutt MoltkeMoesvei31 0316Oslo,Norway e-mail:[email protected] Homepage: http:Hwww.math.uio.no/-bratteli/ ProfessorDerekW. Robinson AustralianNationalUniversity SchoolofMathematicalSciences ACT0200Canberra,Australia e-mail:[email protected] Homepage: http:Hwwwmaths.anu.edu.au/-derek/ LibraryofCongressCataloging-in-PublicationData Bratteli,Ola. Operatoralgebrasandquantumstatisticalmechanics.(Textsandmonographsinphysics) Bibliography;v. 1, p. Includesindex. Contents:v.1.C*-andW*-algebras,symmetrygroups,decompositionofstates. 1.Operator algebras. 2.Statisticalmechanics. 3.Quantumstatistics. 1.Robinson,DerekW.H.Title. III.Series. QA326.B74 1987 512'.55 86-27877 SecondEdition 1987. SecondPrinting2002 ISSN0172-5998 ISBN3-540-17093-6 2ndEdition Springer-VerlagBerlinHeidelbergNewYork This workis subject to copyright.Allrights arereserved, whetherthe whole orpartofthematerial is concerned, specificallytherightsoftranslation,reprinting,reuseofillustrations,recitation,broadcasting,reproductiononmicrofilm orinanyotherway,andstorageindatabanks.Duplicationofthispublicationorpartsthereofispermittedonlyunder theprovisionsoftheGermanCopyrightLawofSeptember9, 1965,initscurrentversion,andpermissionforusemust alwaysbeobtainedfromSpringer-Verlag.ViolationsareliableforprosecutionundertheGermanCopyrightLaw. Springer-VerlagBerlinHeidelbergNewYork amemberofBertelsmannSpringerScience+BusinessMediaGmbH http://www.spfinger.de 0Springer-VerlagBerlinHeidelberg1979,1987 PrintedinGermany Theuseofgeneraldescriptivenames,registerednames,trademarks,etc.inthispublicationdoesnotimply,eveninthe absenceofaspecificstatement,thatsuchnamesareexemptfromtherelevantprobreaktectivelawsandregulationsand thereforefreeforgeneraluse. Coverdesign:design&productionGmbH,Heidelberg Printedonacid-freepaper SPIN 10885981 55/3141/ba 5 4 3 2 1 0 Preface to the Second Printing of the Second Edition Inthis secondprinting ofthe secondedition severalminorandonemajormathe- matical mistake have been corrected. We are indebted to Roberto Conti, Sindre Duedahl andReinhardSchaflitzelforpointingtheseout. CanberraandTrondheim, 2002 OlaBratteli DerekW. Robinson Preface to the Second Edition The second edition ofthis book differs from the original in threerespects. First, we have eliminated a large number of typographical errors. Second, we have corrected a small number ofmathematical oversights. Third, we have rewritten severalsubsectionsinordertoincorporateneworimprovedresults. Theprincipal changes occurinChapters 3 and4. In Chapter 3, Section 3.1.2 now contains a more comprehensive discussion ofdissipative operators and analytic elements. Additions and changes have also been made in Sections 3.1.3, 3.1.4, and 3.1.5. Further improvements occur in Section3.2.4. InChapter4the only substantialchanges areto Sections4.2.1 and 4.2.2. At the time of writing the first edition it was an open question whether maximal orthogonal probability measures on the state space of a C*-algebra were automatically maximal among all the probability measures on the space. This question was resolved positively in 1979 and the rewritten sections now incorporatetheresult. All these changes are nevertheless revisionary in nature and do not change the scope of the original edition. In particular, we have resisted the temptation to describe the developments ofthe last seven years in the theory ofderivations, anddissipations, associatedwithC*-dynamical systems. Thecurrentstateofthis theoryissummarizedin [[Bra 1]] publishedinSpringer-Verlag'sLectureNotesin Mathematics series. CanberraandTrondheim, 1986 OlaBratteli DerekW. Robinson v Preface to the First Edition In this book we describe the elementary theory of operator algebras and parts of the advanced theory which are of relevance, or potentially of relevance, to mathematical physics. Subsequently we describe various applications to quantum statistical mechanics. At the outset ofthis project weintendedtocoverthismaterialinonevolumebutinthecourseofdevelop- mentitwasrealizedthatthiswouldentailtheomissionofvariousinteresting topics or details. Consequently the book was split into two volumes, the firstdevoted tothegeneraltheoryofoperatoralgebrasandthesecondto the applications. This splitting into theory and applications is conventional but somewhat arbitrary. In the last 15-20 years mathematical physicists have realized the importance of operator algebras and their states and automorphisms for problems offieldtheoryand statisticalmechanics. Butthetheoryof20years ago was largely developed for the analysis ofgroup representations and it was inadequate for many physical applications. Thus after a short honey- moonperiodinwhichthenewfoundtools ofthe extant theorywereapplied to themostamenableproblemsalongerandmore interestingperiodensued in which mathematical physicists were forced to redevelop the theory in relevant directions. New concepts were introduced, e.g. asymptotic abelian- ness and KMS states, new techniques applied, e.g. the Choquet theory of barycentric decomposition for states, and new structural results obtained, e.g. the existence ofa continuum ofnonisomorphic type-three factors. The resultsofthisperiodhadasubstantialimpactonthesubsequentdevelopment ofthe theory ofoperator algebras and led to a continuing period offruitful Vil viii Preface to the First Edition collaboration between mathematicians and physicists. They also led to an intertwining ofthe theory and applications in which the applications often forced the formation ofthe theory. Thus in this context the division ofthis book has a certain arbitrariness. Thetwovolumesofthebookcontainsixchapters, fourinthisfirstvolume and two in the second. The chapters of the second volume are numbered consecutively with those of the first and the references are cumulative. Chapter I is a brief historical introduction and it is the five subsequent chaptersthatformthemain bodyofmaterial. We have encountered various difficultiesinourattemptstosynthesizethismaterialintoonecoherentbook. Firstlythereare broad variations in the natureand difficulty ofthe different chapters. This is partly because the subject matter lies between the main- streamsofpuremathematicsandtheoreticalphysicsandpartlybecauseitisa mixture of standard theory and research work which has not previously appearedinbookform.Wehavetriedtointroduceauniformityandstructure and we hope the reader will find our attempts are successful. Secondly the range oftopics relevant to quantum statistical mechanics is certainly more extensive than our coverage. For example we have completely omitted discussion of open systems, irreversibility, and semi-groups of completely positive maps because these topics have been treated in other recent mono- graphs [[Dav 1]] [[Eva 1]]. This book was written between September 1976 and July t979. Most ofChapters 1-5 were written whilst the authors were in Marseille at the Universit6 d'Aix-Marseille 11, Luminy, and the Centre de Physique Th6orique CNRS. During a substantial part ofthis period 0. Bratteli was supported by the Norwegian Research Council for Science and Humanities and during the complementary period by a post of"ProfesseurAssoci6" at Luminy. Chapter 6 was partially written at the University of New South Wales and partially in Marseille and at the University ofOslo. Chapters2, 3,4andhalfofChapter5weretypedattheCentredePhysique Th6orique, CNRS, Marseille. Most of the remainder was typed at the Department ofPure Mathematics, University ofNew South Wales. It is a pleasure to thank Mlle. Maryse Cohen-Solal, Mme. Dolly Roche, and Mrs. Mayda Shahinian for their work. We have profited from discussions with many colleagues throughout the preparation ofthe manuscript. We are grateful to Gavin Brown, Ed Effros, George Elliott, Uffe Haagerup, Richard Herman, Daniel Kastler, Akitaka Kishimoto, John Roberts, Ray Streater and Andr6 Verbeure for helpful comments and corrections to earlier versions. We are particularly indebted to Adam Majewski for reading the final manuscript and locating numerous errors. Oslo andSydney, 1979 Ola Bratteli Derek W. Robinson Contents (Volume 1) Introduction Notesand Remarks 16 C*-Algebras and von Neumann Algebras 17 2.1. C* -Algebras 19 2.1.1. BasicDefinitionsand Structure 19 2.2. FunctionalandSpectralAnalysis 25 2.2.1. Resolvents, Spectra, and Spectral Radius 25 2.2.2. Positive Elements 32 2.2.3. Approximate Identitiesand QuotientAlgebras 39 2.3. RepresentationsandStates 42 2.3.1. Representations 42 2.3.2. States 48 2.3.3. Construction ofRepresentations 54 2.3.4. ExistenceofRepresentations 58 2.3.5. Commutative C*-Algebras 61 ix x Contents (Volume t) 2.4. vonNeumannAlgebras 65 2.4.1. Topologies on Y(.5) 65 2.4.2. Definitionand ElementaryPropertiesofvonNeumannAlgebras 71 2.4.3. Normal StatesandthePredual 75 2.4.4. Quasi-EquivalenceofRepresentations 79 2.5. Tomita-TakesakiModularTheoryandStandardFormsofvonNeumann Algebras 83 2.5.1. a-FinitevonNeumannAlgebras 84 2.5.2. The ModularGroup 86 2.5.3. IntegrationandAnalytic ElementsforOne-ParameterGroupsof Isometrieson Banach Spaces 97 2.5.4. Self-Dual Conesand Standard Forms 102 2.6. Quasi-LocalAlgebras 118 2.6.1. ClusterProperties 118 2.6.2. Topological Properties 129 2.6.3. AlgebraicProperties 133 2.7. MiscellaneousResultsandStructure 136 2.7.1. Dynamical SystemsandCrossedProducts 136 2.7.2. TensorProductsofOperatorAlgebras 142 2.7.3. Weights on Operator Algebras; Self-Dual Cones of General von Neumann Algebras; Duality and Classification ofFactors; Classification ofC*-Algebras 145 NotesandRemarks 152 Groups, Sernigroups, and Generators 157 3.1. BanachSpaceTheory 159 3.1.1. Uniform Continuity 161 3.1.2. Strong, Weak, andWeak* Continuity 163 3.1.3. ConvergenceProperties t84 3.1.4. PerturbationTheory t93 3.1.5. ApproximationTheory 202 3.2. AlgebraicTheory 209 209 3.2.1. PositiveLinearMapsandJordan Morphisms 233 3.2.2. GeneralPropertiesofDerivations