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Mathematics
Topology
1. Introduction to Topological Concepts
2. Point-Set Topology
3. Algebraic Topology
4. Differential Topology
5. Geometric Topology
6. Advanced Topics
Algebraic Topology
Homotopy Theory
Homotopy of Maps
Definition of Homotopy
Homotopy as Equivalence Relation
Homotopy Classes
Homotopy of Paths
Path Homotopy
Homotopy Relative to Endpoints
Homotopy Equivalence
Homotopy Equivalent Spaces
Homotopy Type
Contractible Spaces
Deformation Retracts
Retractions
Definition of Retraction
Strong Deformation Retracts
Examples and Applications
Homotopy Extension Property
Definition and Applications
CW Complexes and HEP
Fundamental Group
Paths and Loops
Definition of Paths
Concatenation of Paths
Inverse Paths
Loops at a Base Point
The Fundamental Group
Group Structure on Homotopy Classes
Associativity and Identity
Inverse Elements
Dependence on Base Point
Change of Base Point
Path-Connected Spaces
Isomorphism of Fundamental Groups
Functoriality
Induced Homomorphisms
Functorial Properties
Computation Examples
Fundamental Group of Circle
Fundamental Group of Sphere
Fundamental Group of Torus
Fundamental Group of Figure Eight
Fundamental Group of Projective Plane
Van Kampen's Theorem
Statement and Applications
Free Products of Groups
Amalgamated Products
Applications
Brouwer Fixed Point Theorem
Fundamental Theorem of Algebra
Classification of Covering Spaces
Covering Spaces
Definition and Examples
Covering Maps
Local Homeomorphisms
Examples of Coverings
Lifting Properties
Path Lifting Lemma
Homotopy Lifting Property
Unique Lifting Property
Universal Covering Spaces
Existence and Construction
Uniqueness up to Isomorphism
Examples of Universal Covers
Deck Transformations
Group of Deck Transformations
Regular Coverings
Galois Correspondence
Classification of Coverings
Correspondence with Subgroups
Covering Space Actions
Higher Homotopy Groups
Definition of πₙ
n-Spheres and Base Points
Group Structure for n ≥ 2
Basic Properties
Abelian Nature for n > 1
Functoriality
Homotopy Groups of Spheres
Low-Dimensional Cases
Hopf Fibrations
Freudenthal Suspension Theorem
Long Exact Sequence
Fibrations and Cofibrations
Exact Sequences in Homotopy
Whitehead's Theorem
Weak Homotopy Equivalences
CW Approximation
Homology Theory
Simplicial Homology
Simplicial Complexes
Oriented Simplices
Chain Groups
Boundary Operators
Homology Groups
Singular Homology
Singular Simplices
Singular Chain Complex
Singular Homology Groups
Functoriality
Properties of Homology
Homotopy Invariance
Dimension Axiom
Exactness Axiom
Relative Homology
Relative Chain Complexes
Long Exact Sequence
Excision Theorem
Mayer-Vietoris Sequence
Statement and Proof
Applications to Computations
Cellular Homology
CW Complexes
Cellular Chain Complex
Cellular Boundary Formula
Homological Algebra
Chain Complexes
Exact Sequences
Snake Lemma
Five Lemma
Euler Characteristic
Definition and Properties
Euler-Poincaré Formula
Topological Applications
Cohomology Theory
Definition of Cohomology
Cochain Complexes
Coboundary Operators
Cohomology Groups
Universal Coefficient Theorem
Relationship between Homology and Cohomology
Ext and Tor Functors
Cup Product
Definition and Properties
Ring Structure on Cohomology
Cohomology of Spaces
Cohomology of Spheres
Cohomology of Projective Spaces
Cohomology of Grassmannians
Poincaré Duality
Statement for Manifolds
Applications and Examples
Čech Cohomology
Definition via Open Covers
Relationship to Singular Cohomology
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4. Differential Topology