Commutative Algebra

Advice for the Beginner.- Information for the Expert.- Prerequisites.- Sources.- Courses.- Acknowledgements.- 0 Elementary Definitions.- 0.1 Rings and Ideals.- 0.2 Unique Factorization.- 0.3 Modules.- I Basic Constructions.- 1 Roots of Commutative Algebra.- 2 Localization.- 3 Associated Primes and Primary Decomposition.- 4 Integral Dependence and the Nullstellensatz.- 5 Filtrations and the Artin-Rees Lemma.- 6 Flat Families.- 7 Completions and Hensel’s Lemma.- II Dimension Theory.- 8 Introduction to Dimension Theory.- 9 Fundamental Definitions of Dimension Theory.- 10 The Principal Ideal Theorem and Systems of Parameters.- 11 Dimension and Codimension One.- 12 Dimension and Hilbert-Samuel Polynomials.- 13 The Dimension of Affine Rings.- 14 Elimination Theory, Generic Freeness, and the Dimension of Fibers.- 15Gröbner Bases.- 16 Modules of Differentials.- III Homological Methods.- 17 Regular Sequences and the Koszul Complex.- 18 Depth, Codimension, and Cohen-Macaulay Rings.- 19 Homological Theory of Regular Local Rings.- 20 Free Resolutions and Fitting Invariants.- 21 Duality, Canonical Modules, and Gorenstein Rings.- Appendix 1 Field Theory.- A1.1 Transcendence Degree.- A1.2 Separability.- A1.3.1 Exercises.- Appendix 2 Multilinear Algebra.- A2.1 Introduction.- A2.2 Tensor Product.- A2.3 Symmetric and Exterior Algebras.- A2.3.1 Bases.- A2.3.2 Exercises.- A2.4 Coalgebra Structures and Divided Powers.- A2.5 Schur Functors.- A2.5.1 Exercises.- A2.6 Complexes Constructed by Multilinear Algebra.- A2.6.1 Strands of the Koszul Comple.- A2.6.2 Exercises.- Appendix 3 Homological Algebra.- A3.1 Introduction.- I: Resolutions and Derived Functors.- A3.2 Free and Projective Modules.- A3.3 Free and Projective Resolutions.- A3.4 Injective Modules and Resolutions.- A3.4.1 Exercises.- Injective Envelopes.- Injective Modules over Noetherian Rings.- A3.5 Basic Constructions with Complexes.- A3.5.1 Notation and Definitions.- A3.6 Maps and Homotopies of Complexes.- A3.7 Exact Sequences ofComplexes.- A3.7.1 Exercises.- A3.8 The Long Exact Sequence in Homology.- A3.8.1 Exercises.- Diagrams and Syzygies.- A3.9 Derived Functors.- A3.9.1 Exercise on Derived Functors.- A3.10 Tor.- A3.10.1 Exercises: Tor.- A3.1l Ext.- A3.11.1 Exercises: Ext.- A3.11.2 Local Cohomology.- II: From Mapping Cones to Spectral Sequences.- A3.12 The Mapping Cone and Double Complexe.- A3.12.1 Exercises: Mapping Cones and Double Complexes.- A3.13 Spectral Sequences.- A3.13.1 Mapping Cones Revisited.- A3.13.2 Exact Couples.- A3.13.3 Filtered Differential Modules and Complexes.- A3.13.4 The Spectral Sequence of a Double Complex.- A3.13.5 Exact Sequence of Terms of Low Degree.- A3.13.6 Exercises on Spectral Sequences.- A3.14 Derived Categories.- A3.14.1 Step One: The Homotopy Category of Complexes.- A3.14.2 Step Two: The Derived Category.- A3.14.3 Exercises on the Derived Category.- Appendix 4 A Sketch of Local Cohomology.- A4.1 Local Cohomology and Global Cohomology.- A4.2 Local Duality.- A4.3 Depth andDimensio.- Appendix 5 Category Theory.- A5.1 Categories, Functors, and Natural Transformations.- A5.2 Adjoint Functors.- A5.2.1 Uniqueness.- A5.2.2 Some Examples.- A5.2.3 Another Characterization of Adjoints.- A5.2.4 Adjoints and Limits.- A5.3 Representable Functors and Yoneda's Lemma.- Appendix 6 Limits and Colimits.- A6.1 Colimits in the Category of Modules.- A6.2 Flat Modules as Colimits of Free Modules.- A6.3 Colimits in the Category of Commutative Algebras.- A6.4 Exercises.- Appendix 7 Where Next?.- References.- Index of Notation.