Complexes and the Cohen-Macaulay Property(复形与Cohen-Macaulay性质)

2024.05.28 271

作者: 武同锁、郭锦

定价: 128.00

出版社: 科学出版社

版次: 1

出版时间:2021年12月

开本: 16

装帧: 1042.00

页数: 254

ISBN编码:978-7-03-070302-6

购买链接:https://item.jd.com/13592936.html

内容介绍:

全书共分为7章。第一章包含了关于深度、Krull维数以及Cohen-Macaulay性质(以下简称CM性质)等的一些核心结果或者基本事实;其中关于标准代数的CM性与分次CM性的等价性、序列CM模的代数描述两部分内容反映了本书的特色。第二章讨论单纯复形的基本事实,特别是描述了两个代数不变量(由复形构造的面环的深度、Krull维数)与复形的拓扑不变量(维数)之间的确切关系)。第三章讨论复形的shellable性质,特别是详细推演其用restriction map进行的等价刻画、与d-可分性之间的等价关系,这是对于shellable性质的深刻描述和讨论。第四章介绍了如何由拓扑复形构造代数链复形,介绍相应的导出同调群,并重点介绍了近代文献中有较多应用的Koszul复形以及来自单项式理想的三种常用代数复形(或正合列)的详尽构造。第五章是本书的核心和重点,全面深刻地介绍CM复形、shellable与CM的关系、线性预解式与线性商以及如何从图出发构造好的拓扑与代数复形。第五章包含了作者最新的研究成果,也综述了多个研究专题(包含作者和业界核心专家的成果)。第六章主要介绍Bejorner等人的近期成果,主要是讨论如何从偏序集出发构造系列的shellable复形等。第七章是专门讨论正则度的,既包含中心的传统结果,也包含了作者等人的近期研究成果。

目录:

Preface

Notations

Chapter 1 Preliminaries on Cohen-Macaulay Rings and Modules ..................................1

    1. Jacobson radical and NAK Lemma..................................2
    2. Modules with finite lengths..................................3
    3. On graded rings and minimal graded free resolution..................................6
    4. Cohen-Macaulay rings and Cohen-Macaulay Modules..................................11
      1. Dimension, height and Krull’s PI theorem..................................11
      2. Depth Lemma and ..................................14
      3. Local rings: Krull dimension and a system of parameters..................................17
      4. Cohen-Macaulay modules and Cohen-Macaulay rings: local case................22
      5. Cohen-Macaulay rings: non-local case..................................26
      6. Cohen-Macaulay rings: graded case..................................28
      7. Gorenstein rings..................................34
    5. Sequentially Cohen-Macaulay modu1es..................................35

Chapter 2 Abstract Simplicial Complexes....................................40

    1. Definitions, fundamiental properties and examples..................................40
      1. Abstract simplex and abstract simplicial complex..................................40
      2. 0ther notations and symbols on a simplicial complex..................................41
      3. Fundamental operations on sub-complexes and geometric realization of an abstract simplicial complex..................................42
    2. The facet ideal and Stanley-Reisner ideal of a simplicial complex ..................................47
      1. Monomial ideals and ideal operations.................................47
      2. The Stanley-Reisner (nonface) ideal and facet ideal ................................47
      3. The Alexander dual simplicial complexofand related properties.................................48
      4. Square-free monomial ideal : its nonface complex, facet complex; and -ideals.................................54
    3. Relative simplicial complexes and relative nonface ideals.................................55

Chapter 3 Shellable Simplicial Complexes.................................57

    1. Destriction and examples.................................57
    2. Restriction maps and Rearrangement Lemmas.................................60
    3. -skeleton .................................64
    4. Shifted, vertex-decomposable and shellable conditions for a simplicial complex.................................66
    5. Shellable and -decomposable.................................69

Chapter 4 Chain Complex Reduced from a Simplicial Complex and Koszul Complexes.................................73

    1. The chain complex reduced from an abstract simplicial complex and reduced homology groups.................................74
    2. Koszul complexes of lengths 1 or 2.................................79
    3. Koszul complexes of geueral length.................................80
      1. Exterior algebra constructed from a module.................................80
      2. Koszul complexes: two commonly used definitions.................................81
    4. Koszul complexes: a summary of main results.................................83
    5. Other resolutions and complexes of monomial ideals.................................84
      1. The Taylor resolution.................................84
      2. The Scarf complex.................................86
      3. The Lyubeznik resolutions.................................89

Chapter 5 (Sequentially) Cohen-Macaulay Simplicial Complexes and Graphs.................................91

    1. Cohen-Macaulay simplicial complexes.................................92
      1. Fundamental properties and characterizations.................................92
      2. Connected in codimension one.................................97
      3. Minimal Cohen-Macaulay simplicial complexes and shelled over.................................100
    2. Matroid complexes.................................104
    3. Pure shellable, constructible, and Cohen-Macaulay.................................107
    4. A graded ideal with linear quotients and shellable complexes.................................111
      1. A graded ideal with linear quotients.................................111
      2. Shellable complexes and monomial ideals having linear quotients.................................115
      3. Powers of edge ideals of graphs and regularity.................................118
      4. A polymatroidal monomial ideal has linear quotients.................................119
      5. Strongly shellable simplicial complexes.................................120
    5. sCM simplicial complexes and sCM graded modules.................................121
    6. Clique complex , edge ideal and cover ideal ................................123
    7. Vertex-decomposable graphs and shellable graphs.................................124
    8. Minimal verex covers and standard irredundant primary decomposition of I(G) .................................127
    9. Cohen-Macaulay graphs and well-covered graphs.................................129
    10. Shellable clutters.................................131
      1. Clutters with the free vertex property.................................132
      2. Chordal clutters.................................133
    11. Some particular classes of graphs.................................133
      1. Bipartite graphs.................................133
      2. Boolean graphs are Cohen-Macaulay 138
      3. Cactus graphs and classes of vertex-decomposable graphs.................................143
      4. Cameron-Walker graphs.................................146
      5. Chordal graphs.................................147
      6. -simplicial complexes and -ideals of kind .................................150
      7. Gap-free graphs and related -free graphs.................................174
      8. Graphs whose complements are -partite.................................176
      9. Graph expansions and graph blow ups.................................185
      10. Interlacing graphs and triangular graphs .................................188
      11. Vertex clique-whiskered graphs and their generalizations .................................189
      12. 1-decomposable graphs.................................202

Chapter 6 Shellable Simplicial Complexes from Posets.................................204

    1. Preliminaries.................................204
    2. A bounded, locally upper-semimodular poset is pure shellable.................................205
    3. EL-labeling of a poset and EL-shellable graded posets.................................209
    4. Admissible lattices and SL-shellable poset.................................213
    5. CL-shellable poset and recursive atom orderings.................................215
      1. Rooted interval and CL-shellable poset.................................216
      2. Recursive atom orderings.................................218

Chapter 7 Betti Numbers and Castelnuovo-Mumford Regularity.................................222

    1. Calculating Betti numbers via the functor Tor.................................222
    2. Polarization keeps the Betti numbers and regularity unchanged.................................224
    3. Hochster’s Formula and other two reformulations.................................226
    4. Graded Betti numbers of graphs: some general reults.................................230
    5. Splittable monomial ideals and Betti splitting.................................231
    6. Miscellanies Results on Betti Numbers.................................232
      1. The join complex of simplicial complexes.................................232
      2. Graded -modules with pure resolutions.................................233
      3. Stable monomial ideals.................................233
      4. Monomial ideals with linear quotients.................................233
      5. Vertex-decomposable simplcial complexes and multiple clique-whiskered graph.................................234
      6. Chordal graphs 235
    7. Castelnuovo-Mumford regularity of graphs.................................235
      1. A brief survey of some general results.................................235
      2. Graphs whose edge ideals have regularity less than 4.................................237

References.................................240

Index.................................248