具体描述
The aim of this book is to explain modern homotopy theory in a manner accessible to graduate students yet structured so that experts can skip over numerous linear developments to quickly reach the topics of their interest. Homotopy theory arises from choosing a class of maps, called weak equivalences, and then passing to the homotopy category by localizing with respect to the weak equivalences, i.e., by creating a new category in which the weak equivalences are isomorphisms. Quillen defined a model category to be a category together with a class of weak equivalences and additional structure useful for describing the homotopy category in terms of the original category. This allows you to make constructions analogous to those used to study the homotopy theory of topological spaces.
A model category has a class of maps called weak equivalences plus two other classes of maps, called cofibrations and fibrations. Quillen's axioms ensure that the homotopy category exists and that the cofibrations and fibrations have extension and lifting properties similar to those of cofibration and fibration maps of topological spaces. During the past several decades the language of model categories has become standard in many areas of algebraic topology, and it is increasingly being used in other fields where homotopy theoretic ideas are becoming important, including modern algebraic K-theory and algebraic geometry.
All these subjects and more are discussed in the book, beginning with the basic definitions and giving complete arguments in order to make the motivations and proofs accessible to the novice. The book is intended for graduate students and research mathematicians working in homotopy theory and related areas.
作者简介
Philip S. Hirschhorn is a mathematician at Wellesley College.
目录信息
Introduction 10
Model categories and their homotopy categories 10
Localizing model category structures 12
Acknowledgments 16
Part 1. Localization of Model Category Structures 18
Summary of Part 1 20
Chapter 1. Local Spaces and Localization 22
1.1. Definitions of spaces and mapping spaces 22
1.2. Local spaces and localization 25
1.3. Constructing an f-localization functor 33
1.4. Concise description of the f-localization 37
1.5. Postnikov approximations 39
1.6. Topological spaces and simplicial sets 41
1.7. A continuous localization functor 46
1.8. Pointed and unpointed localization 48
Chapter 2. The Localization Model Category for Spaces 52
2.1. The Bousfield localization model category structure 52
2.2. Subcomplexes of relative ∧{f}-cell complexes 54
2.3. The Bousfield-Smith cardinality argument 59
Chapter 3. Localization of Model Categories 64
3.1. Left localization and right localization 64
3.2. C-local objects and C-local equivalences 68
3.3. Bousfield localization 74
3.4. Bousfield localization and properness 82
3.5. Detecting equivalences 85
Chapter 4. Existence of Left Bousfield Localizations 88
4.1. Existence of left Bousfield localizations 88
4.2. Horns on S and S-local equivalences 90
4.3. A functorial localization 91
4.4. Localization of subcomplexes 93
4.5. The Bousfield-Smith cardinality argument 95
4.6. Proof of the main theorem 98
Chapter 5. Existence of Right Bousfield Localizations 100
5.1. Right Bousfield localization: Cellularization 100
5.2. Horns on K and K-colocal equivalences 102
5.3. K-colocal cofibrations 104
5.4. Proof of the main theorem 106
5.5. K-colocal objects and K-cellular objects 107
Chapter 6. Fiberwise Localization 110
6.1. Fiberwise localization 110
6.2. The fiberwise local model category structure 112
6.3. Localizing the fiber 112
6.4. Uniqueness of the fiberwise localization 115
Part 2. Homotopy Theory in Model Categories 118
Summary of Part 2 120
Chapter 7. Model Categories 124
7.1. Model categories 125
7.2. Lifting and the retract argument 127
7.3. Homotopy 132
7.4. Homotopy as an equivalence relation 136
7.5. The classical homotopy category 139
7.6. Relative homotopy and fiberwise homotopy 142
7.7. Weak equivalences 146
7.8. Homotopy equivalence 147
7.9. The equivalence relation generated by "weak equivalence'' 150
7.10. Topological spaces and simplicial sets 151
Chapter 8. Fibrant and Cofibrant Approximations 154
8.1. Fibrant and cofibrant approximations 155
8.2. Approximations and homotopic maps 161
8.3. The homotopy category of a model category 164
8.4. Derived functors 168
8.5. Quillen functors and total derived functors 170
Chapter 9. Simplicial Model Categories 176
9.1. Simplicial model categories 176
9.2. Colimits and limits 180
9.3. Weak equivalences of function complexes 181
9.4. Homotopy lifting 184
9.5. Simplicial homotopy 187
9.6. Uniqueness of lifts 192
9.7. Detecting weak equivalences 194
9.8. Simplicial functors 196
Chapter 10. Ordinals, Cardinals, and Transfinite Composition 202
10.1. Ordinals and cardinals 203
10.2. Transfinite composition 205
10.3. Transfinite composition and lifting in model categories 210
10.4. Small objects 211
10.5. The small object argument 213
10.6. Subcomplexes of relative I-cell complexes 218
10.7. Cell complexes of topological spaces 221
10.8. Compactness 223
10.9. Effective monomorphisms 225
Chapter 11. Cofibrantly Generated Model Categories 226
11.1. Cofibrantly generated model categories 227
11.2. Cofibrations in a cofibrantly generated model category 228
11.3. Recognizing cofibrantly generated model categories 230
11.4. Compactness 232
11.5. Free cell complexes 234
11.6. Diagrams in a cofibrantly generated model category 241
11.7. Diagrams in a simplicial model category 242
11.8. Overcategories and undercategories 243
11.9. Extending diagrams 245
Chapter 12. Cellular Model Categories 248
12.1. Cellular model categories 248
12.2. Subcomplexes in cellular model categories 249
12.3. Compactness in cellular model categories 251
12.4. Smallness in cellular model categories 252
12.5. Bounding the size of cell complexes 253
Chapter 13. Proper Model Categories 256
13.1. Properness 256
13.2. Properness and lifting 260
13.3. Homotopy pullbacks and homotopy fiber squares 261
13.4. Homotopy fibers 266
13.5. Homotopy pushouts and homotopy cofiber squares 267
Chapter 14. The Classifying Space of a Small Category 270
14.1. The classifying space of a small category 271
14.2. Cofinal functors 273
14.3. Contractible classifying spaces 275
14.4. Uniqueness of weak equivalences 277
14.5. Categories of functors 280
14.6. Cofibrant approximations and fibrant approximations 283
14.7. Diagrams of undercategories and overcategories 285
14.8. Free cell complexes of simplicial sets 288
Chapter 15. The Reedy Model Category Structure 294
15.1. Reedy categories 295
15.2. Diagrams indexed by a Reedy category 298
15.3. The Reedy model category structure 305
15.4. Quillen functors 311
15.5. Products of Reedy categories 311
15.6. Reedy diagrams in a cofibrantly generated model category 313
15.7. Reedy diagrams in a cellular model category 319
15.8. Bisimplicial sets 320
15.9. Cosimplicial simplicial sets 322
15.10. Cofibrant constants and fibrant constants 325
15.11. The realization of a bisimplicial set 329
Chapter 16. Cosimplicial and Simplicial Resolutions 334
16.1. Resolutions 335
16.2. Quillen functors and resolutions 340
16.3. Realizations 341
16.4. Adjointness 343
16.5. Homotopy lifting extension theorems 348
16.6. Frames 354
16.7. Reedy frames 359
Chapter 17. Homotopy Function Complexes 364
17.1. Left homotopy function complexes 366
17.2. Right homotopy function complexes 367
17.3. Two-sided homotopy function complexes 369
17.4. Homotopy function complexes 371
17.5. Functorial homotopy function complexes 374
17.6. Homotopic maps of homotopy function complexes 379
17.7. Homotopy classes of maps 382
17.8. Homotopy orthogonal maps 384
17.9. Sequential colimits 393
Chapter 18. Homotopy Limits in Simplicial Model Categories 396
18.1. Homotopy colimits and homotopy limits 397
18.2. The homotopy limit of a diagram of spaces 400
18.3. Coends and ends 402
18.4. Consequences of adjoint ness 406
18.5. Homotopy invariance 411
18.6. Simplicial objects and cosimplicial objects 412
18.7. The Bousfield-Kan map 413
18.8. Diagrams of pointed or unpointed spaces 415
18.9. Diagrams of simplicial sets 417
Chapter 19. Homotopy Limits in General Model Categories 422
19.1. Homotopy colimits and homotopy limits 422
19.2. Coends and ends 424
19.3. Consequences of adjoint ness 428
19.4. Homotopy invariance 431
19.5. Homotopy pullbacks and homotopy pushouts 433
19.6. Homotopy cofinal functors 435
19.7. The Reedy diagram homotopy lifting extension theorem 440
19.8. Realizations and total objects 443
19.9. Reedy cofibrant diagrams and Reedy fibrant diagrams 444
Index 446
Bibliography 472
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