List of abstract algebra topics
Abstract algebra is the subject area of mathematics that studies algebraic structures, such as groups, rings, fields, modules, vector spaces, and algebras. The phrase abstract algebra was coined at the turn of the 20th century to distinguish this area from what was normally referred to as algebra, the study of the rules for manipulating formulae and algebraic expressions involving unknowns and real or complex numbers, often now called elementary algebra. The distinction is rarely made in more recent writings.
Basic language
Algebraic structures are defined primarily as sets with operations.
- Algebraic structure
- Subobjects: subgroup, subring, subalgebra, submodule etc.
- Binary operation
- Closure of an operation
- Associative property
- Distributive property
- Commutative property
- Unary operator
- Finitary operation
Structure preserving maps called homomorphisms are vital in the study of algebraic objects.
- Homomorphisms
- Kernels and cokernels
- Image and coimage
- Epimorphisms and monomorphisms
- Isomorphisms
- Isomorphism theorems
- Isomorphisms
There are several basic ways to combine algebraic objects of the same type to produce a third object of the same type. These constructions are used throughout algebra.
- Direct sum
- Direct product
- Quotient objects: quotient group, quotient ring, quotient module etc.
- Tensor product
Advanced concepts:
- Category theory
- Category of groups
- Category of rings
- Category of modules
- Category of vector spaces
- Homological algebra
- Filtration (algebra)
- Exact sequence
- Functor
- Zorn's lemma
Semigroups and monoids
- Semigroup
- Subsemigroup
- Free semigroup
- Green's relations
- Inversion semigroup (cf. )
- Krohn–Rhodes theory
- Semigroup algebra
- Transformation semigroup
- Monoid
- Aperiodic monoid
- Free monoid
- Monoid (category theory)
- Monoid factorisation
- Syntactic monoid
Group theory
- Structure
- Constructions
- Free group
- Quotient group
- Extension problem
- Direct sum, direct product
- Semidirect product
- Types
- Simple group
- Finite group
- Abelian group
- Cyclic group
- Solvable group
- Nilpotent group
- Divisible group
- Dedekind group, Hamiltonian group
- Examples
- Applications
- Group action
- Conjugacy class
- Inner automorphism
- Conjugate closure
- Stabilizer subgroup
- Orbit (group theory)
- Orbit-stabilizer theorem
- Cayley's theorem
- Burnside's lemma
- Burnside's problem
- Loop group
- Fundamental group
Ring theory
- General
- Ring (mathematics)
- Commutative algebra, Commutative ring
- Ring theory, Noncommutative ring
- Algebra over a field
- Relatives to rings: Semiring, Nearring, Rig (algebra)
- Structure
- Subring, Subalgebra
- Ring ideal
- Principal ideal
- Ideal quotient
- Maximal ideal, minimal ideal
- Primitive ideal, prime ideal, semiprime ideal
- Radical of an ideal
- Jacobson radical
- Socle of a ring
- unit (ring theory), Idempotent, Nilpotent, Zero divisor
- Characteristic (algebra)
- Ring homomorphism, Algebra homomorphism
- Ring epimorphism
- Ring monomorphism
- Ring isomorphism
- Graded algebra
- Morita equivalence
- Constructions
- Direct sum of rings, Product of rings
- Quotient ring
- Matrix ring
- Endomorphism ring
- Polynomial ring
- Formal power series
- Monoid ring, Group ring
- Localization of a ring
- Tensor algebra
- Free algebra
- Completion (ring theory)
- Types
- Field (mathematics), Division ring, division algebra
- Simple ring, Central simple algebra, Semisimple ring, Semisimple algebra
- Primitive ring, Semiprimitive ring
- Prime ring, Semiprime ring, Reduced ring
- Integral domain, Domain (ring theory)
- Von Neumann regular ring
- Quasi-Frobenius ring
- Hereditary ring, Semihereditary ring
- Local ring, Semi-local ring
- Discrete valuation ring
- Regular local ring
- Cohen–Macaulay ring
- Gorenstein ring
- Artinian ring, Noetherian ring
- Perfect ring, semiperfect ring
- Baer ring, Rickart ring
- Lie ring, Lie algebra
- Ideal (Lie algebra)
- Jordan algebra
- Differential algebra
- Banach algebra
- Examples
- Theorems and applications
- Algebraic geometry
- Hilbert's basis theorem
- Hopkins–Levitzki theorem
- Krull's principal ideal theorem
- Levitzky's theorem
- Galois theory
- Artin-Wedderburn theorem
- Jacobson density theorem
- Wedderburn's little theorem
- Lasker–Noether theorem
Field theory
- Basic concepts
- Field (mathematics)
- Subfield (mathematics)
- Multiplicative group
- Primitive element (field theory)
- Multiplicative group
- Field extension
- Field norm
- Field trace
- Conjugate element (field theory)
- Tensor product of fields
- Types
- Algebraic number field
- Global field
- Local field
- Finite field
- Symmetric function
- Formally real field
- Real closed field
- Applications
Module theory
- General
- Structure
- Submodule
- Module homomorphism
- Essential submodule
- Superfluous submodule
- Singular submodule
- Socle of a module
- Radical of a module
- Constructions
- Free module
- Quotient module
- Direct sum, Direct product of modules
- Direct limit, Inverse limit
- Localization of a module
- Completion (ring theory)
- Types
- Simple module, Semisimple module
- Indecomposable module
- Artinian module, Noetherian module
- Homological types:
- Coherent module
- Finitely-generated module
- Finitely-presented module
- Finitely related module
- Algebraically compact module
- Reflexive module
- Concepts and theorems
- Composition series
- Structure theorem for finitely generated modules over a principal ideal domain
- Homological dimension
- Projective dimension
- Injective dimension
- Flat dimension
- Global dimension
- Weak global dimension
- Cohomological dimension
- Krull dimension
- Regular sequence (algebra), depth (algebra)
- Fitting lemma
- Schur's lemma
- Nakayama's lemma
- Krull–Schmidt theorem
- Steinitz exchange lemma
- Jordan–Hölder theorem
- Artin–Rees lemma
- Schanuel's lemma
- Morita equivalence
Representation theory
Representation theory
Non-associative systems
- General
- Associative property, Associator
- Heap (mathematics)
- Magma (algebra)
- Loop (algebra), Quasigroup
- Nonassociative ring, Non-associative algebra
- Universal enveloping algebra
- Lie algebra (see also list of Lie group topics and list of representation theory topics)
- Jordan algebra
- Alternative algebra
- Power associativity
- Flexible algebra
- Examples
Generalities
- Algebraic structure
- Universal algebra
- Variety (universal algebra)
- Congruence relation
- Free object
- Generating set (universal algebra)
- Clone (algebra)
- Kernel of a function
- Kernel (algebra)
- Isomorphism class
- Isomorphism theorem
- Fundamental theorem on homomorphisms
- Universal property
- Filtration (mathematics)
- Category theory
- Monoidal category
- Groupoid
- Group object
- Coalgebra
- Bialgebra
- Hopf algebra
- Magma object
- Torsion (algebra)
Computer algebra
- Symbolic mathematics