Concepts

A mathematical idea. It can have more than one definition.

Ideas 1951–2100 of 5206.

Name	Kind	Subject
Strong Cesàro summability	Concept	Sequences, series, summability
Finite difference coefficients	Concept	Numerical analysis
Turing machine	Concept	Mathematical logic and foundations
Iterated function system	Concept	Measure and integration
Complete Boolean algebra	Concept	Order, lattices, ordered algebraic structures
Classical group	Concept	Group theory and generalizations
Real Hardy space H1	Concept	Harmonic analysis on Euclidean spaces
Finitely presented algebra	Concept	Commutative algebra
Projection operation	Concept	General algebraic systems
Cellular algebra	Concept	Associative rings and algebras
Positive operator	Concept	Operator theory
Real closure	Concept	Field theory and polynomials
Kelvin functions	Concept	Special functions
Coupled map lattice	Concept	Dynamical systems and ergodic theory
Product measure	Concept	Measure and integration
Calderón–Zygmund kernel	Concept	Harmonic analysis on Euclidean spaces
Annihilator method	Concept	Ordinary differential equations
Summability field of a matrix method	Concept	Sequences, series, summability
Rogers–Ramanujan continued fraction	Concept	Number theory
Morse–Smale system	Concept	Dynamical systems and ergodic theory
Oval	Concept	Geometry
Brouwer–Heyting–Kolmogorov interpretation	Concept	Mathematical logic and foundations
Darboux function	Concept	Real functions
p-harmonic function	Concept	Potential theory
Steiner system	Concept	Combinatorics
Nonlinear difference equation	Concept	Difference and functional equations
Chebyshev polynomials of the second kind	Concept	Special functions
Riemannian manifold	Concept	Differential geometry
Subalgebra	Concept	Associative rings and algebras
A priori estimate	Concept	Partial differential equations
Arithmetical hierarchy	Concept	Mathematical logic and foundations
Runge–Kutta methods	Concept	Numerical analysis
Thin set	Concept	Potential theory
Haken manifold	Concept	Manifolds and cell complexes
Manifold with boundary	Concept	Manifolds and cell complexes
Barnes G-function	Concept	Special functions
Simple polytope	Concept	Convex and discrete geometry
Jacobson ring	Concept	Commutative algebra
Whittaker function	Concept	Special functions
Quantum calculus	Concept	Combinatorics
Jackson integral	Concept	Combinatorics
Partially ordered ring	Concept	Order, lattices, ordered algebraic structures
Moufang plane	Concept	Geometry
Quantifier elimination	Concept	Mathematical logic and foundations
Point spectrum	Concept	Operator theory
Schwarz–Christoffel mapping	Concept	Functions of a complex variable
Attractor	Concept	Dynamical systems and ergodic theory
k-vertex-connected graph	Concept	Combinatorics
Minkowski sum of polytopes	Concept	Convex and discrete geometry
Hausdorff topological group	Concept	Topological groups, Lie groups
Holonomic function	Concept	Special functions
Rogers polynomials	Concept	Special functions
Characteristic class	Concept	Algebraic topology
Kähler differentials	Concept	Commutative algebra
Numerical integration	Concept	Numerical analysis
Representation of a Lie group	Concept	Topological groups, Lie groups
Lie group	Concept	Topological groups, Lie groups
Invertible sheaf	Concept	Algebraic geometry
Curvature of a curve	Concept	Differential geometry
Diffeology	Concept	Global analysis, analysis on manifolds
Finite difference	Concept	Difference and functional equations
Crystallographic group	Concept	Group theory and generalizations
Level-set method	Concept	Numerical analysis
Bernstein–Sato polynomial	Concept	Algebraic geometry
Quadratic functional equation	Concept	Difference and functional equations
Rectifiable set	Concept	Measure and integration
Best approximation	Concept	Approximations and expansions
Semihereditary ring	Concept	Associative rings and algebras
Dedekind domain	Concept	Commutative algebra
Irreducible ideal	Concept	Commutative algebra
Combinatorial species	Concept	Combinatorics
Germ of a holomorphic function	Concept	Several complex variables and analytic spaces
Whitney C-infinity topology	Concept	Global analysis, analysis on manifolds
Irreducible matrix	Concept	Linear and multilinear algebra; matrix theory
Vanishing moments of a wavelet	Concept	Harmonic analysis on Euclidean spaces
Harmonic analysis	Concept	Harmonic analysis on Euclidean spaces
Chern connection	Concept	Differential geometry
Allen–Cahn equation	Concept	Partial differential equations
Unitization	Concept	Functional analysis
Sum-free set	Concept	Number theory
Reverse mathematics	Concept	Mathematical logic and foundations
Quadratic field	Concept	Number theory
Germ of a smooth function	Concept	Global analysis, analysis on manifolds
Direct limit of algebras	Concept	General algebraic systems
LF-space	Concept	Functional analysis
Cone	Concept	Category theory; homological algebra
Directed-complete partial order	Concept	Order, lattices, ordered algebraic structures
Lebesgue constant	Concept	Approximations and expansions
Irreducible analytic germ	Concept	Several complex variables and analytic spaces
Stably finite ring	Concept	Associative rings and algebras
Ring with involution	Concept	Associative rings and algebras
Comodule	Concept	Associative rings and algebras
Mixed-type equation	Concept	Partial differential equations
Simple function	Concept	Measure and integration
Tame Fréchet space	Concept	Functional analysis
Sturm–Liouville theory	Concept	Ordinary differential equations
Parallelizable manifold	Concept	Manifolds and cell complexes
Decomposition group	Concept	Number theory
Quasilinear PDE	Concept	Partial differential equations
Method of characteristics	Concept	Partial differential equations
Dirichlet character	Concept	Number theory
Hopf algebra	Concept	Associative rings and algebras
Error function	Concept	Special functions
Extraspecial group	Concept	Group theory and generalizations
Artin–Schreier theory	Concept	Field theory and polynomials
Tropical geometry	Concept	Algebraic geometry
Zernike polynomials	Concept	Special functions
Étale cohomology	Concept	Algebraic geometry
Transformation semigroup	Concept	Group theory and generalizations
Sine-Gordon equation	Concept	Partial differential equations
Operational calculus	Concept	Integral transforms, operational calculus
Moore family	Concept	Order, lattices, ordered algebraic structures
Levi form	Concept	Several complex variables and analytic spaces
Subnormal operator	Concept	Operator theory
Euler summation	Concept	Sequences, series, summability
Arithmetic geometry	Concept	Algebraic geometry
Wave front of a Legendrian map	Concept	Differential geometry
Envelope	Concept	Differential geometry
Følner condition	Concept	Abstract harmonic analysis
Mikusiński field of operators	Concept	Integral transforms, operational calculus
Chern–Weil homomorphism	Concept	Differential geometry
Brill–Noether theory	Concept	Algebraic geometry
Reduced complex space	Concept	Several complex variables and analytic spaces
Regular open set	Concept	General topology
Riesz kernel energy	Concept	Potential theory
Down-closure	Concept	Order, lattices, ordered algebraic structures
Domino tiling	Concept	Combinatorics
Sparse grid	Concept	Numerical analysis
p-adic gamma function	Concept	Number theory
Spline	Concept	Approximations and expansions
Morphism	Concept	Category theory; homological algebra
Injective module	Concept	Commutative algebra
Homogeneous space	Concept	Algebraic geometry
Classifying topos	Concept	Category theory; homological algebra
Abstract data type as an algebra	Concept	Computer science
Adjoint of an unbounded operator	Concept	Operator theory
F-space	Concept	Functional analysis
Coercive bilinear form	Concept	Operator theory
f-vector	Concept	Convex and discrete geometry
Polytope combinatorics	Concept	Convex and discrete geometry
Hyperkähler manifold	Concept	Differential geometry
Heun function	Concept	Special functions
Mixed finite element method	Concept	Numerical analysis
Height of a prime ideal	Concept	Commutative algebra
Subdirect product	Concept	General algebraic systems
Schrödinger operator	Concept	Ordinary differential equations
Diagonally dominant matrix	Concept	Linear and multilinear algebra; matrix theory
Hereditary ring	Concept	Associative rings and algebras
Tracy–Widom distribution	Concept	Probability theory and stochastic processes
Dual object	Concept	Category theory; homological algebra