15 More on Algebra
- Section 15.1: Introduction
- Section 15.2: Advice for the reader
- Section 15.3: Stably free modules
- Section 15.4: A comment on the Artin-Rees property
- Section 15.5: Fibre products of rings, I
- Section 15.6: Fibre products of rings, II
- Section 15.7: Fibre products of rings, III
- Section 15.8: Fitting ideals
- Section 15.9: Lifting
- Section 15.10: Zariski pairs
- Section 15.11: Henselian pairs
- Section 15.12: Henselization of pairs
- Section 15.13: Lifting and henselian pairs
- Section 15.14: Absolute integral closure
- Section 15.15: Auto-associated rings
-
Section 15.16: Flattening stratification
- Lemma 15.16.1
- Section 15.17: Flattening over an Artinian ring
- Section 15.18: Flattening over a closed subset of the base
- Section 15.19: Flattening over a closed subsets of source and base
- Section 15.20: Flattening over a Noetherian complete local ring
- Section 15.21: Descent of flatness along integral maps
- Section 15.22: Torsion free modules
-
Section 15.23: Reflexive modules
- Definition 15.23.1
- Lemma 15.23.2
- Lemma 15.23.3
- Lemma 15.23.4
- Lemma 15.23.5
- Lemma 15.23.6
- Lemma 15.23.7
- Lemma 15.23.8
- Definition 15.23.9
- Lemma 15.23.10
- Lemma 15.23.11
- Lemma 15.23.12
- Lemma 15.23.13
- Lemma 15.23.14
- Lemma 15.23.15
- Lemma 15.23.16
- Example 15.23.17
- Lemma 15.23.18
- Lemma 15.23.19
- Lemma 15.23.20
- Section 15.24: Content ideals
- Section 15.25: Flatness and finiteness conditions
- Section 15.26: Blowing up and flatness
- Section 15.27: Completion and flatness
- Section 15.28: The Koszul complex
- Section 15.29: The extended alternating Čech complex
- Section 15.30: Koszul regular sequences
- Section 15.31: More on Koszul regular sequences
- Section 15.32: Regular ideals
- Section 15.33: Local complete intersection maps
- Section 15.34: Cartier's equality and geometric regularity
- Section 15.35: Geometric regularity
- Section 15.36: Topological rings and modules
- Section 15.37: Formally smooth maps of topological rings
- Section 15.38: Formally smooth maps of local rings
- Section 15.39: Some results on power series rings
- Section 15.40: Geometric regularity and formal smoothness
- Section 15.41: Regular ring maps
- Section 15.42: Ascending properties along regular ring maps
- Section 15.43: Permanence of properties under completion
- Section 15.44: Permanence of properties under étale maps
- Section 15.45: Permanence of properties under henselization
- Section 15.46: Field extensions, revisited
- Section 15.47: The singular locus
- Section 15.48: Regularity and derivations
- Section 15.49: Formal smoothness and regularity
- Section 15.50: G-rings
- Section 15.51: Properties of formal fibres
- Section 15.52: Excellent rings
- Section 15.53: Abelian categories of modules
-
Section 15.54: Injective abelian groups
- Lemma 15.54.1
- Section 15.55: Injective modules
- Section 15.56: Derived categories of modules
- Section 15.57: Computing Tor
- Section 15.58: Tensor products of complexes
- Section 15.59: Derived tensor product
- Section 15.60: Derived change of rings
- Section 15.61: Tor independence
- Section 15.62: Spectral sequences for Tor
- Section 15.63: Products and Tor
- Section 15.64: Pseudo-coherent modules, I
- Section 15.65: Pseudo-coherent modules, II
- Section 15.66: Tor dimension
- Section 15.67: Spectral sequences for Ext
- Section 15.68: Projective dimension
- Section 15.69: Injective dimension
- Section 15.70: Modules which are close to being projective
- Section 15.71: Hom complexes
- Section 15.72: Sign rules
- Section 15.73: Derived hom
- Section 15.74: Perfect complexes
- Section 15.75: Lifting complexes
- Section 15.76: Splitting complexes
- Section 15.77: Recognizing perfect complexes
- Section 15.78: Characterizing perfect complexes
- Section 15.79: Strong generators and regular rings
- Section 15.80: Relatively finitely presented modules
- Section 15.81: Relatively pseudo-coherent modules
- Section 15.82: Pseudo-coherent and perfect ring maps
- Section 15.83: Relatively perfect modules
- Section 15.84: Two term complexes
- Section 15.85: The naive cotangent complex
- Section 15.86: Rlim of abelian groups
- Section 15.87: Rlim of modules
- Section 15.88: Torsion modules
-
Section 15.89: Formal glueing of module categories
- Lemma 15.89.1
- Lemma 15.89.2
- Lemma 15.89.3
- Lemma 15.89.4
- Lemma 15.89.5
- Lemma 15.89.6
- Lemma 15.89.7
-
Lemma 15.89.8
- Equation 15.89.8.1
- Lemma 15.89.9
- Remark 15.89.10
- Lemma 15.89.11
- Lemma 15.89.12
- Lemma 15.89.13
- Lemma 15.89.14
- Lemma 15.89.15
- Proposition 15.89.16
- Lemma 15.89.17
- Theorem 15.89.18
- Proposition 15.89.19
- Remark 15.89.20
- Remark 15.89.21
-
Section 15.90: The Beauville-Laszlo theorem
- Lemma 15.90.1
- Lemma 15.90.2
- Lemma 15.90.3
- Lemma 15.90.4 reference
- Remark 15.90.5
- Lemma 15.90.6
- Remark 15.90.7
- Remark 15.90.8
- Example 15.90.9
- Lemma 15.90.10
- Remark 15.90.11
- Example 15.90.12: Non glueable module reference
- Lemma 15.90.13
- Lemma 15.90.14
- Lemma 15.90.15 reference
-
Theorem 15.90.16
reference
- Equation 15.90.16.1
- Equation 15.90.16.2
- Equation 15.90.16.3
- Remark 15.90.17
- Lemma 15.90.18
- Lemma 15.90.19
- Remark 15.90.20
-
Section 15.91: Derived Completion
- Lemma 15.91.1
- Lemma 15.91.2
- Lemma 15.91.3
- Definition 15.91.4
- Proposition 15.91.5
- Lemma 15.91.6
- Lemma 15.91.7
- Lemma 15.91.8
- Lemma 15.91.9
- Lemma 15.91.10 slogan
- Remark 15.91.11
- Lemma 15.91.12
- Lemma 15.91.13
- Lemma 15.91.14
- Situation 15.91.15
- Lemma 15.91.16
- Lemma 15.91.17
- Lemma 15.91.18
- Lemma 15.91.19 slogan reference
- Lemma 15.91.20
- Lemma 15.91.21
- Example 15.91.22
- Lemma 15.91.23
- Lemma 15.91.24
-
Section 15.92: The category of derived complete modules
- Lemma 15.92.1
- Section 15.93: Derived completion for a principal ideal
- Section 15.94: Derived completion for Noetherian rings
- Section 15.95: An operator introduced by Berthelot and Ogus
- Section 15.96: Perfect complexes and the eta operator
- Section 15.97: Taking limits of complexes
- Section 15.98: Some evaluation maps
- Section 15.99: Base change for derived hom
- Section 15.100: Systems of modules
- Section 15.101: Systems of modules, bis
- Section 15.102: Miscellany
- Section 15.103: Tricks with double complexes
-
Section 15.104: Weakly étale ring maps
- Definition 15.104.1
- Lemma 15.104.2
- Definition 15.104.3
- Lemma 15.104.4
- Lemma 15.104.5
- Lemma 15.104.6
- Lemma 15.104.7
- Lemma 15.104.8
- Lemma 15.104.9
- Lemma 15.104.10
- Lemma 15.104.11
- Lemma 15.104.12
- Lemma 15.104.13
- Lemma 15.104.14
- Lemma 15.104.15
- Lemma 15.104.16
- Lemma 15.104.17
- Lemma 15.104.18
- Lemma 15.104.19
- Lemma 15.104.20
- Lemma 15.104.21
- Lemma 15.104.22
- Lemma 15.104.23
- Theorem 15.104.24: Olivier
- Section 15.105: Weakly étale algebras over fields
- Section 15.106: Local irreducibility
- Section 15.107: Miscellaneous on branches
- Section 15.108: Branches of the completion
- Section 15.109: Formally catenary rings
- Section 15.110: Group actions and integral closure
- Section 15.111: Extensions of discrete valuation rings
- Section 15.112: Galois extensions and ramification
- Section 15.113: Krasner's lemma
- Section 15.114: Abhyankar's lemma and tame ramification
-
Section 15.115: Eliminating ramification
- Definition 15.115.1
- Example 15.115.2
- Lemma 15.115.3
- Lemma 15.115.4
- Lemma 15.115.5
- Lemma 15.115.6
- Lemma 15.115.7
- Lemma 15.115.8
- Lemma 15.115.9
- Lemma 15.115.10
- Lemma 15.115.11
- Lemma 15.115.12
- Lemma 15.115.13
- Lemma 15.115.14
- Lemma 15.115.15
-
Lemma 15.115.16
- Equation 15.115.16.1
- Equation 15.115.16.2
- Lemma 15.115.17
- Theorem 15.115.18: Epp
- Section 15.116: Eliminating ramification, II
- Section 15.117: Picard groups of rings
- Section 15.118: Determinants
- Section 15.119: Perfect complexes and K-groups
- Section 15.120: Determinants of endomorphisms of finite length modules
- Section 15.121: A regular local ring is a UFD
- Section 15.122: Determinants of complexes
- Section 15.123: Extensions of valuation rings
- Section 15.124: Structure of modules over a PID
- Section 15.125: Principal radical ideals
- Section 15.126: Invertible objects in the derived category
- Section 15.127: Splitting off a free module
- Section 15.128: Big projective modules are free