Every idea

Ideas 5551–5700 of 14183.

Name	Kind	Subject
Ehresmann's fibration theorem	Theorem	Global analysis, analysis on manifolds
A priori estimate	Concept	Partial differential equations
Semimodular lattice	Definition	Order, lattices, ordered algebraic structures
Arithmetical hierarchy	Concept	Mathematical logic and foundations
Frobenius method	Definition	Ordinary differential equations
Torus integral	Definition	Several complex variables and analytic spaces
Runge–Kutta methods	Concept	Numerical analysis
Integral scheme	Definition	Algebraic geometry
Dixon elliptic functions	Definition	Special functions
Kunen's inconsistency theorem	Theorem	Mathematical logic and foundations
Congruence generated by a relation	Definition	General algebraic systems
Thin set	Concept	Potential theory
Wreath product	Definition	Group theory and generalizations
Purely transcendental extension	Definition	Field theory and polynomials
Freudenthal suspension theorem	Theorem	Algebraic topology
Optimal truncation	Definition	Approximations and expansions
Haken manifold	Concept	Manifolds and cell complexes
Manifold with boundary	Concept	Manifolds and cell complexes
Elementary class	Definition	Mathematical logic and foundations
Quadratic field	Definition	Number theory
Barnes G-function	Concept	Special functions
Artin–Mazur zeta function	Definition	Dynamical systems and ergodic theory
Simple polytope	Concept	Convex and discrete geometry
Quasi-isomorphism	Definition	Category theory; homological algebra
Neutral differential equation	Definition	Ordinary differential equations
Reaction–diffusion system	Definition	Partial differential equations
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
Finite morphism	Definition	Algebraic geometry
Oscillatory integral	Definition	Harmonic analysis on Euclidean spaces
Mittag-Leffler star	Definition	Functions of a complex variable
Ornstein–Uhlenbeck process	Definition	Probability theory and stochastic processes
First variation	Definition	Calculus of variations and optimal control; optimization
Markov theorem	Theorem	Manifolds and cell complexes
Moufang plane	Concept	Geometry
Liouville property of graphs	Definition	Potential theory
The integers modulo 2 and the group of signs are isomorphic	Example	Group theory and generalizations
Quantifier elimination	Concept	Mathematical logic and foundations
Point spectrum	Concept	Operator theory
Purely inseparable extension	Definition	Field theory and polynomials
Schwarz–Christoffel mapping	Concept	Functions of a complex variable
Attractor	Concept	Dynamical systems and ergodic theory
Fort space	Counterexample	General topology
Radical extension	Definition	Field theory and polynomials
k-vertex-connected graph	Concept	Combinatorics
Thom–Mather isotopy lemmas	Theorem	Global analysis, analysis on manifolds
Kodaira embedding theorem	Theorem	Several complex variables and analytic spaces
The exponential map from the additive reals to the positive reals	Example	Group theory and generalizations
Serre's problem on projective modules	Problem	Commutative algebra
Complex projective space	Example	Several complex variables and analytic spaces
Minkowski sum of polytopes	Concept	Convex and discrete geometry
Hausdorff topological group	Concept	Topological groups, Lie groups
Sphere theorem	Theorem	Differential geometry
Identity theorem in several variables	Theorem	Several complex variables and analytic spaces
Normal fan	Definition	Convex and discrete geometry
Kernel regression	Definition	Statistics
Schaefer's fixed point theorem	Theorem	Operator theory
Holonomic function	Concept	Special functions
Enriques surface	Definition	Algebraic geometry
Modular representation theory	Definition	Group theory and generalizations
Rogers polynomials	Concept	Special functions
Mairhuber–Curtis theorem	Theorem	Approximations and expansions
Characteristic class	Concept	Algebraic topology
Kähler differentials	Concept	Commutative algebra
Jacobson radical	Definition	Commutative algebra
Numerical integration	Concept	Numerical analysis
Mertens' theorems	Theorem	Number theory
Representation of a Lie group	Concept	Topological groups, Lie groups
Lie group	Concept	Topological groups, Lie groups
Invertible sheaf	Concept	Algebraic geometry
Pseudospectrum	Definition	Numerical analysis
Smoothing spline	Definition	Numerical analysis
Curvature of a curve	Concept	Differential geometry
Diffeology	Concept	Global analysis, analysis on manifolds
Finite difference	Concept	Difference and functional equations
Local homeomorphism	Definition	General topology
Thue–Morse sequence	Object	Number theory
Bessel–Clifford function	Definition	Special functions
Wu's formula	Theorem	Manifolds and cell complexes
Lp space	Definition	Functional analysis
Dirac comb	Example	Harmonic analysis on Euclidean spaces
Regularity structures	Definition	Probability theory and stochastic processes
Simple algebra	Definition	General algebraic systems
Bifurcation from a characteristic value	Definition	Operator theory
von Neumann's inequality	Theorem	Operator theory
Crystallographic group	Concept	Group theory and generalizations
Level-set method	Concept	Numerical analysis
KdV equation as an integrable system	Example	Dynamical systems and ergodic theory
Bernstein–Sato polynomial	Concept	Algebraic geometry
Method of lines	Definition	Numerical analysis
Omitting types theorem	Theorem	Mathematical logic and foundations
Morse homology	Definition	Manifolds and cell complexes
Ideal norm	Definition	Number theory
Braided monoidal category	Definition	Category theory; homological algebra
Quadratic functional equation	Concept	Difference and functional equations
Rectifiable set	Concept	Measure and integration
Best approximation	Concept	Approximations and expansions
Quillen–Suslin theorem	Theorem	Commutative algebra
Near-unanimity term	Definition	General algebraic systems
Peano kernel theorem	Theorem	Approximations and expansions
Semihereditary ring	Concept	Associative rings and algebras
Dedekind domain	Concept	Commutative algebra
Sturm–Liouville theory	Definition	Ordinary differential equations
L-infinity space	Definition	Functional analysis
Irreducible ideal	Concept	Commutative algebra
Combinatorial species	Concept	Combinatorics
Germ of a holomorphic function	Concept	Several complex variables and analytic spaces
Riesz kernel energy	Definition	Potential theory
Whitney C-infinity topology	Concept	Global analysis, analysis on manifolds
Group C*-algebra	Definition	Topological groups, Lie groups
Fitting subgroup	Definition	Group theory and generalizations
Irreducible matrix	Concept	Linear and multilinear algebra; matrix theory
Ore condition	Definition	Associative rings and algebras
Weak lower semicontinuity	Definition	Calculus of variations and optimal control; optimization
Vanishing moments of a wavelet	Concept	Harmonic analysis on Euclidean spaces
Stone's theorem on paracompactness of metric spaces	Theorem	General topology
Kummer's 24 solutions	Theorem	Special functions
Sheaf	Definition	General topology
Harmonic analysis	Concept	Harmonic analysis on Euclidean spaces
Trapezoidal rule	Definition	Numerical analysis
Smale–Hirsch theorem	Theorem	Manifolds and cell complexes
Regular prime	Definition	Number theory
Chern connection	Concept	Differential geometry
Hilbert's twenty-first problem	Problem	Ordinary differential equations
Eisenstein series as a double series	Example	Sequences, series, summability
Gödel numbering	Definition	Mathematical logic and foundations
Delsarte linear programming bound	Theorem	Convex and discrete geometry
Pontryagin's maximum principle	Theorem	Calculus of variations and optimal control; optimization
Lanczos algorithm	Theorem	Numerical analysis
Allen–Cahn equation	Concept	Partial differential equations
Unitization	Concept	Functional analysis
Stein's example	Counterexample	Statistics
Homotopy equivalence	Definition	Algebraic topology
Sum-free set	Concept	Number theory
Mal'cev condition	Definition	General algebraic systems
Reverse mathematics	Concept	Mathematical logic and foundations
Sylvester's determinant identity	Theorem	Linear and multilinear algebra; matrix theory
Quadratic field	Concept	Number theory
Germ of a smooth function	Concept	Global analysis, analysis on manifolds
Censoring	Definition	Statistics
Direct limit of algebras	Concept	General algebraic systems
Class VII surface	Definition	Several complex variables and analytic spaces
Regularity theory	Definition	Partial differential equations
Bayes estimator	Definition	Statistics
Paley–Wiener theorem for Volterra resolvents	Theorem	Integral equations
Fredholm determinant	Definition	Integral equations
X-ray transform	Definition	Integral transforms, operational calculus