Every idea

Ideas 12301–12450 of 14167.

Name	Kind	Subject
Hyers–Ulam stability	Concept	Difference and functional equations
Lang's conjectures	Conjecture	Algebraic geometry
Cyclic polytope	Definition	Convex and discrete geometry
Lemniscate elliptic functions	Concept	Special functions
Local regression	Concept	Statistics
Simplicial approximation theorem	Theorem	Algebraic topology
Coplanarity	Definition	Geometry
Supermanifold	Definition	Global analysis, analysis on manifolds
Reverse mathematics	Definition	Mathematical logic and foundations
Root-finding algorithm	Concept	Numerical analysis
Tame Fréchet space	Definition	Functional analysis
Closure of an operator	Concept	Operator theory
Jacobi polynomials	Concept	Special functions
Pitchfork bifurcation	Definition	Ordinary differential equations
Sato–Tate conjecture	Theorem	Number theory
Jet	Definition	Global analysis, analysis on manifolds
Endomorphism ring of a simple module is a division ring	Corollary	Associative rings and algebras
Hankel matrix	Definition	Linear and multilinear algebra; matrix theory
Ill-posedness of real Laplace inversion	Concept	Integral transforms, operational calculus
Gauss sum	Definition	Number theory
No-three-in-line problem	Problem	Convex and discrete geometry
Gromov–Hausdorff convergence	Definition	Differential geometry
Lindelöf's maximum principle	Lemma	Potential theory
Topological ring	Concept	Associative rings and algebras
Pick matrix	Concept	Functions of a complex variable
Discrete Fourier transform	Concept	Numerical analysis
Strict hyperbolicity	Definition	Partial differential equations
Elimination theory	Definition	Commutative algebra
Initial algebra	Definition	Category theory; homological algebra
Logicism	Definition	Mathematical logic and foundations
Partial correlation	Concept	Statistics
Meromorphic function of several variables	Definition	Several complex variables and analytic spaces
Robinson arithmetic	Definition	Mathematical logic and foundations
Riesz representation theorem	Theorem	Functional analysis
Stokes phenomenon	Concept	Ordinary differential equations
Spectral density estimation	Concept	Statistics
Quantum calculus	Definition	Combinatorics
Absolutely free algebra	Concept	General algebraic systems
Kolmogorov's three-series theorem	Theorem	Probability theory and stochastic processes
Atom	Concept	Order, lattices, ordered algebraic structures
Bianchi identities	Theorem	Differential geometry
Locally finite poset	Concept	Order, lattices, ordered algebraic structures
Parallel transport	Concept	Differential geometry
Orientability	Definition	Manifolds and cell complexes
Boole's rule	Theorem	Numerical analysis
Dual pair	Definition	Functional analysis
Poincaré recurrence theorem	Theorem	Dynamical systems and ergodic theory
Congruence-permutable variety	Definition	General algebraic systems
Torsion tensor	Definition	Differential geometry
Serial ring	Concept	Associative rings and algebras
Measurable solutions of Cauchy's equation	Theorem	Difference and functional equations
Quantum logic	Definition	Quantum theory
Cyclotomic extension	Definition	Field theory and polynomials
Finite type invariant	Concept	Manifolds and cell complexes
Étale fundamental group	Definition	Algebraic geometry
Continuous-time Markov chain	Concept	Probability theory and stochastic processes
Deck transformation group	Definition	Manifolds and cell complexes
Frostman's theorem	Theorem	Potential theory
Čech cohomology	Definition	Algebraic topology
Beurling–Ahlfors transform	Concept	Harmonic analysis on Euclidean spaces
JSJ decomposition	Theorem	Manifolds and cell complexes
Contiguous relations	Theorem	Special functions
Riemann zeta function	Definition	Number theory
Asymmetric simple exclusion process	Example	Probability theory and stochastic processes
K-function	Concept	Special functions
Structure theorem for finitely generated modules over a principal ideal domain	Theorem	Commutative algebra
Link	Definition	Manifolds and cell complexes
Summation in topological groups	Concept	Sequences, series, summability
Forward difference operator	Definition	Difference and functional equations
Representation of a quiver	Concept	Associative rings and algebras
Measure problem of Lebesgue	Problem	Measure and integration
Morita equivalence of Lie groupoids	Definition	Topological groups, Lie groups
Strange attractor	Definition	Dynamical systems and ergodic theory
Banach analytic space	Concept	Several complex variables and analytic spaces
Von Neumann–Bernays–Gödel set theory	Definition	Mathematical logic and foundations
Basel problem via Fourier series	Example	Harmonic analysis on Euclidean spaces
Kepler problem	Example	Mechanics of particles and systems
Subdirectly irreducible algebra	Definition	General algebraic systems
Neville theta functions	Concept	Special functions
Complementary error function	Concept	Special functions
Gaussian binomial coefficient	Definition	Combinatorics
Simplicial object	Definition	Category theory; homological algebra
Measurable Riemann mapping theorem	Theorem	Functions of a complex variable
Adjoint functors	Concept	Category theory; homological algebra
Temperley–Lieb algebra	Concept	Associative rings and algebras
Cohen's theorem on Noetherian rings	Theorem	Commutative algebra
Disjoint union of posets	Concept	Order, lattices, ordered algebraic structures
Fourier monomial on the circle	Concept	Harmonic analysis on Euclidean spaces
Hadamard three-circle theorem	Theorem	Functions of a complex variable
Primary ideal	Definition	Commutative algebra
Unital	Concept	Geometry
Triangulation of a point set	Concept	Convex and discrete geometry
Radical ideal	Definition	Commutative algebra
Internal set theory	Concept	Mathematical logic and foundations
Valuation on convex bodies	Concept	Convex and discrete geometry
Clifford–Klein form	Definition	Manifolds and cell complexes
Capacity equals transfinite diameter and Chebyshev constant	Theorem	Potential theory
Box–Jenkins method	Definition	Statistics
Fuglede's theorem	Theorem	Operator theory
Fredholm equation of the first kind	Definition	Integral equations
Radical of a module	Definition	Associative rings and algebras
Kolmogorov continuity theorem	Theorem	Probability theory and stochastic processes
Schur decomposition	Theorem	Linear and multilinear algebra; matrix theory
Compact-open topology	Definition	General topology
Completion of a topological group	Concept	Topological groups, Lie groups
Schwarz–Pick theorem	Theorem	Functions of a complex variable
Voronoi cell	Concept	Convex and discrete geometry
Cointegration	Concept	Statistics
G-delta set	Concept	General topology
Z-transform	Definition	Integral transforms, operational calculus
Auslander–Reiten quiver	Definition	Associative rings and algebras
Wiener's Tauberian theorem	Theorem	Abstract harmonic analysis
Tverberg's theorem	Theorem	Convex and discrete geometry
1 − 1 + 2 − 6 + 24 − 120 + ⋯	Example	Sequences, series, summability
Mapping cylinder	Definition	Algebraic topology
Genus	Definition	Manifolds and cell complexes
Term algebra	Definition	General algebraic systems
Banach–Lie group	Definition	Topological groups, Lie groups
Singular values of a compact operator	Definition	Operator theory
Bessel potential	Concept	Potential theory
Weil's local rigidity theorem	Theorem	Topological groups, Lie groups
Pin group	Example	Topological groups, Lie groups
Tight frame	Concept	Harmonic analysis on Euclidean spaces
Epsilon-net of a set system	Concept	Convex and discrete geometry
Lewy extension theorem	Theorem	Several complex variables and analytic spaces
Homotopy invariance of homology	Theorem	Algebraic topology
Caccioppoli set	Definition	Calculus of variations and optimal control; optimization
Heap	Concept	Group theory and generalizations
Full subcategory	Concept	Category theory; homological algebra
Eilenberg–Zilber theorem	Theorem	Algebraic topology
Mapping cone	Definition	Category theory; homological algebra
No small subgroups	Definition	Topological groups, Lie groups
Causal inference	Concept	Statistics
Polar polytope	Definition	Convex and discrete geometry
Solvable Lie group	Definition	Topological groups, Lie groups
Lerch's uniqueness theorem	Theorem	Integral transforms, operational calculus
Regular local rings are domains	Theorem	Commutative algebra
Cubic spline	Concept	Approximations and expansions
Lattice congruence	Definition	Order, lattices, ordered algebraic structures
Trace of an integral operator	Definition	Integral equations
Complex structure on the six-sphere	Problem	Several complex variables and analytic spaces
Skolem–Noether theorem	Theorem	Associative rings and algebras
Factorial experiment	Definition	Statistics
Cayley–Klein metric	Definition	Geometry
Lemniscate constant	Object	Special functions
Abel's summation formula	Theorem	Sequences, series, summability
Dynkin system	Concept	Measure and integration
Perron–Wiener–Brelot solution	Definition	Potential theory
Rigidity of frameworks	Concept	Convex and discrete geometry
Interpolation space	Definition	Functional analysis