內容簡介
This textbook is designed to introduce advanced undergraduate or beginning graduate students to algebraic topology as painlessly as possible. The principal topics treated are 2-dimensional manifolds, the fundamental group, and covering spaces, plus the group theory needed in these topics. The only prerequisites are some group theory, such as that normally contained in an undergraduate algebra course on the junior-senior level, and a one-semester undergraduate course in general topology.
The topics discussed in this book are "standard" in the sense that several well-known textbooks and treatises devote a few sections or a chapter to them. This, I believe, is the first textbook giving a straightforward treatment of these topics, stripped of all unnecessary definitions, terminology, etc., and with numerous examples and exercises, thus making them intelligible to advanced undergraduate students.
內頁插圖
目錄
CHAPTERONETwo-DimensionalManifolds
1 Introduction
2 Definitionandexamplesofn-manifolds
3 Orientablevs.nonorientablemanifolds
4 Examplesofcompact,connected2-manifolds
5 Statementoftheclassificationtheoremforcompactsurfaces
6 Triangulationsofcompactsurfaces
7 ProofofTheorem5.1
8 TheEulercharacteristicofasurface
9 Manifoldswithboundary
10 Theclassificationofcompact,connected2-manifoldswithboundary
11 TheEulercharacteristicofaborderedsurface
12 ModelsofcompactborderedsurfacesinEuclidean3-space
13 Remarksonnoncompactsurfaces
CHAPTERTWOTheFundamentalGroup
1 Introduction
2 Basicnotationandterminology
3 Definitionofthefundamentalgroupofaspace
4 Theeffectofacontinuousmai)pingonthefundamentalgroup
5 Thefundamentalgroupofacircleisinfinitecyclic
6 Application:TheBrouwerfixed-pointtheoremilldimension2
7 Thefundamentalgroupofaproductspace
8 Homotopytypeandhomotopyequivalenceofspaces
CHAPTERTHREEFreeGroupsandFreeProductsofGroups
1 Introduction
2 Theweakproductofabeliangroups
3 Freeabeliangroups
4 Freeproductsofgroups
5 Freegroups
6 Thepresentationofgroupsbygeneratorsandrelations
7 Universalmappingproblems
CHAPTERFOURScifertandVanKampenTheoremontheFundamentalGroupoftheUnionofTwoSpaces.Applic
ations
1 Introduction
2 StatementandproofofthetheoremofSeifertandVanKampen
3 FirstapplicationofTheorem2.1
4 SecondapplicationofTheorem2.1
5 Structureofthefundamentalgroupofacompactsurface
6 Applicationtoknottheory
CHAPTERFIVECoveringSpaces
1 Introduction
2 Definitionandsomeexamplesofcoveringspaces
3 Liftingofpathstoacoveringspace
4 Thefundamentalgroupofacoveringspace
5 Liftingofarbitrarymapstoacoveringspace
6 Homomorphismsandautomorphismsofcoveringspaces
7 Theactionofthegroupπ(X,x)onthesetp-(x)
8 Regularcoveringspacesandquotientspaces
9 Application:TheBorsuk-Ulamtheoremforthe2-sphere
10 Theexistencetheoremforcoveringspaces
11 Theinducedcoveringspaceoverasubspace
12 Pointsettopologyofcoveringspaces
CHAPTERSIXTheFundamentalGroupandCoveringSpacesofaGraph.ApplicationstoGroupTheory
1 Introduction
2 Definitionandexamples
3 Basicpropertiesofgraphs
4 Trees
5 Thefundamentalgroupofagraph
6 TheEulercharacteristicofafinitegraph
7 Coveringspacesofagraph
8 Generatorsforasubgroupoffreegroup
CHAPTERSEVENTheFundamentalGroupofHigherDimensionalSpaces
1 Introduction
2 Adjunctionof2-cellstoaspace
3 Adjunctionofhigherdimensionalcellstoaspace
4 CW-complexes
5 TheKuroshsubgrouptheorem
6 GrushkosTheorem
CHAPTEREIGHTEpilogue
APPENDIXATheQuotientSpaceorIdentificationSpaceTopology
1 Definitionsandbasicproperties
2 Ageneralizationofthequotientspacetopology
3 Quotientspacesandproductspaces
4 Subspaceofaquotientspacevs.quotientspaceofasubspace
5 ConditionsforaquotientspacetobeaHausdorffspace
APPENDIXBPermutationGroupsorTransformationGroups
1 Basicdefinitions
2 HomogeneousG-spaces
Index
前言/序言
This textbook iS designed to introduce advanced undergraduate or beginning graduate students to algebraic topology as painlessly as pos- sible.The principal topics treated are 2.dimcnsional manifolds.the fundamental group,and covering spaces,plus the group theory needed in these topics.The only prerequisites are some group theory,such as that normally centained jn an undergraduate algebra course on the junior-senior level,and a one·semester undergraduate course in general topology.
The topics discussed in this book are“standard”in the sense that several well-known textbooks and treatises devote a fey.r sections or a chapter to them.This。I believe,iS the first textbook giving a straight- forward treatment of these topics。stripped of all unnecessary definitions, terminology,etc.,and with numerous examples and exercises,thus making them intelligible to advanced undergraduate students.
The SUbject matter i8 used in several branches of mathematics other than algebraic topology,such as differential geometry,the theory of Lie groups,the theory of Riemann surfaces。or knot theory.In the develop- merit of the theory,there is a nice interplay between algebra and topology which causes each to reinfoFee interpretations of the other.Such an interplay between different topics of mathematics breaks down the often artificial subdivision of mathematics into difierent“branches”and emphasizes the essential unity of all mathematics.
《非綫性動力學與混沌:從經典到現代的探索》 內容簡介 本書旨在全麵深入地探討非綫性動力學理論及其在自然科學、工程技術和社會科學中的廣泛應用。本書的視角著眼於超越傳統綫性係統分析範疇的復雜係統行為,重點闡述混沌、分岔、孤子以及復雜網絡動力學等核心概念。全書結構清晰,由淺入深,旨在為不同學科背景的研究者和高年級本科生、研究生提供一套紮實的理論框架和豐富的案例分析。 第一部分:動力學係統的基礎迴顧與非綫性引言 本部分首先簡要迴顧瞭常微分方程(ODE)和泛函微分方程(FDE)在描述物理係統中的基本作用,並引入相空間(Phase Space)的概念。隨後,本書迅速過渡到非綫性係統的核心議題:為什麼需要非綫性理論?通過對簡單的二次、三次非綫性項的分析,展示瞭綫性化方法在描述係統長期行為時的局限性。 核心內容包括: 相圖與不動點分析: 詳細討論瞭一維和二維自治係統的相平麵分析技術,包括鞍點、節點、焦點(穩定與不穩定)的分類。 極限環的齣現: 深入分析瞭霍普夫(Hopf)分岔的原理,解釋瞭周期性振蕩是如何從穩定不動點“誕生”的,並引入瞭Poincaré截麵用於分析高維係統的周期解。 穩定性理論的深化: 闡述瞭李雅普諾夫(Lyapunov)穩定性和漸近穩定性的精確定義,並介紹瞭構造李雅普諾夫函數的技巧,特彆是對於難以解析求解的復雜係統。 第二部分:混沌的起源與識彆 混沌是本書的重點之一,本部分緻力於揭示確定性係統中看似隨機行為的內在機製。 分岔理論的精細化: 倍周期分岔(Period-Doubling): 詳細考察費根鮑姆(Feigenbaum)常數,闡釋瞭從周期一到周期二、周期四……的過渡過程,這是通往混沌的關鍵路徑之一。 鞍結分岔(Saddle-Node)與意大利麵分岔(Fold Bifurcation): 分析瞭在參數空間中周期解的齣現與消失的拓撲結構變化。 滯後現象(Hysteresis): 在非對稱係統中,通過參數變化觀察到的不同路徑依賴性。 混沌的量化描述: 龐加萊截麵(Poincaré Sections): 作為一個降維工具,用於識彆吸引子的結構,區分周期運動、準周期運動和混沌運動。 李雅普諾夫指數(Lyapunov Exponents): 作為衡量鄰近軌道分離速度的定量指標,本書詳細推導瞭最大李雅普諾夫指數的計算方法,並解釋瞭正的指數是混沌的判據。 信息維度與豪斯多夫維度: 介紹瞭刻畫奇異吸引子復雜性的維度概念,包括關聯維(Correlation Dimension)和信息維,用以區分不同類型的混沌吸引子。 第三部分:奇異吸引子與結構特徵 本部分聚焦於混沌運動在相空間中形成的復雜幾何結構——奇異吸引子。 洛倫茲吸引子(The Lorenz Attractor): 以經典的氣象模型為例,細緻剖析瞭蝴蝶狀吸引子的形成過程,包括其拓撲結構、非整數維度,以及對初始條件的敏感依賴性(“蝴蝶效應”的數學基礎)。 羅森布拉特-洛特卡-沃爾泰拉係統(Rössler System): 作為比洛倫茲係統更簡單的(但在拓撲上等價的)吸引子模型,用於清晰展示螺鏇管的扭麯和摺疊過程。 拓撲混閤性與拓撲熵: 引入拓撲動力學的觀點,討論係統如何混閤相空間中的不同區域,以及拓撲熵作為衡量係統復雜性的更深層指標。 第四部分:空間演化與模式形成 本書的視野拓展到偏微分方程(PDE)描述的係統,關注空間結構如何自發形成。 反應-擴散係統(Reaction-Diffusion Systems): 引入圖靈(Turing)模式的理論基礎,探討激活劑與抑製劑的相互作用如何導緻斑點、條紋等空間結構(形態發生)。 孤波與激波(Solitons and Shocks): 分析非綫性對波傳播的影響。重點介紹KdV方程(Korteweg-de Vries equation)中孤波的穩定性及其背後的代數守恒律,並對比分析激波在耗散係統中的形成。 模式的穩定性與波的穩定性: 討論已形成的周期性空間結構(如行波)抵抗外部擾動或內部波動的能力。 第五部分:復雜性、網絡與應用展望 最後一部分將非綫性動力學置於更廣闊的背景下進行討論。 耦閤振子係統(Coupled Oscillators): 研究大量振子通過某種連接拓撲相互作用時展現齣的集體行為,如同步現象(Synchronization)。詳細討論瞭Kuramoto模型及其在神經科學、電網穩定性中的應用。 網絡拓撲對動力學的影響: 探討異構網絡(如小世界網絡、無標度網絡)與全耦閤網絡在同步速度、混沌傳播效率上的差異。 應用案例精選: 選取瞭生物節律的建模、金融時間序列的非綫性分析、以及氣候係統中的混沌區段等實際工程和科學問題,展示理論工具的實用價值。 本書力求在嚴謹的數學推導和直觀的物理圖像之間取得平衡,通過大量的圖示和算例,幫助讀者真正掌握非綫性動力學這門處理復雜世界的有力工具。