Every idea

Ideas 6901–7050 of 14183.

Name	Kind	Subject
Margulis normal subgroup theorem	Theorem	Topological groups, Lie groups
Besicovitch almost periodic function	Concept	Harmonic analysis on Euclidean spaces
Sidon set	Concept	Number theory
Rayleigh–Ritz method	Definition	Calculus of variations and optimal control; optimization
Sheaf on a site	Definition	Category theory; homological algebra
Substitution tiling	Concept	Dynamical systems and ergodic theory
Hyperbolic triangle	Definition	Geometry
Lagrange inversion theorem	Theorem	Combinatorics
Rademacher functions	Definition	Harmonic analysis on Euclidean spaces
Ring spectrum	Concept	Algebraic topology
Cofinality	Concept	Mathematical logic and foundations
Flag manifold	Concept	Algebraic geometry
Néron–Severi group	Definition	Algebraic geometry
Differentiation operator p	Concept	Integral transforms, operational calculus
Hyperbolic Dehn surgery theorem	Theorem	Manifolds and cell complexes
Artin's conjecture on primitive roots	Conjecture	Number theory
Bergman metric	Concept	Several complex variables and analytic spaces
Semitopological group	Definition	Topological groups, Lie groups
Dynkin's π-λ theorem	Theorem	Measure and integration
Expander graph	Definition	Combinatorics
Rank of an abelian group	Definition	Group theory and generalizations
Wang tile	Example	Convex and discrete geometry
Dynamical system	Concept	Dynamical systems and ergodic theory
Arthur–Selberg trace formula	Theorem	Number theory
Jordan–Hölder theorem for modular lattices	Theorem	Order, lattices, ordered algebraic structures
Iterative functional equation	Concept	Difference and functional equations
H-space	Definition	Algebraic topology
Densely defined operator	Concept	Operator theory
Varadhan's lemma	Lemma	Probability theory and stochastic processes
Lambda calculus	Concept	Mathematical logic and foundations
Azuma's inequality	Theorem	Probability theory and stochastic processes
Selberg trace formula	Theorem	Number theory
Tautological line bundle	Concept	Algebraic geometry
Integration operator as convolution with the unit step	Proposition	Integral transforms, operational calculus
Interior algebra	Concept	Order, lattices, ordered algebraic structures
Fréchet manifold	Definition	Global analysis, analysis on manifolds
Final value theorem	Theorem	Integral transforms, operational calculus
Multiply transitive group action	Concept	Group theory and generalizations
Energy drift	Concept	Numerical analysis
Topological entropy	Concept	Dynamical systems and ergodic theory
Gaussian free field	Definition	Probability theory and stochastic processes
Parry measure	Definition	Dynamical systems and ergodic theory
Conjugacy of maximal tori	Theorem	Topological groups, Lie groups
Arithmetic dynamics	Concept	Dynamical systems and ergodic theory
Yang–Baxter equation	Definition	Associative rings and algebras
Weitzenböck identity	Theorem	Differential geometry
Whitney sum	Concept	Algebraic topology
Uniformly convex space	Concept	Functional analysis
Artin–Schreier theory	Definition	Field theory and polynomials
Kernel density estimation	Definition	Statistics
Eta invariant	Definition	Global analysis, analysis on manifolds
Class field theory	Concept	Number theory
Pólya's recurrence theorem	Theorem	Probability theory and stochastic processes
Vertex of a polytope	Definition	Convex and discrete geometry
Brauer group	Concept	Associative rings and algebras
Hardy–Littlewood maximal inequality	Theorem	Harmonic analysis on Euclidean spaces
Type and cotype	Concept	Functional analysis
Cartesian closed category	Concept	Category theory; homological algebra
Radical axis	Concept	Geometry
Projective module	Concept	Commutative algebra
Jacobson's conjecture	Conjecture	Associative rings and algebras
Empirical likelihood	Concept	Statistics
Schlegel diagram	Definition	Convex and discrete geometry
Nevanlinna theory of difference equations	Definition	Difference and functional equations
Dehn–Lickorish theorem	Theorem	Manifolds and cell complexes
Bellows conjecture	Theorem	Convex and discrete geometry
Benz plane	Concept	Geometry
Kaplansky's theorem on projective modules	Theorem	Associative rings and algebras
Fagin's theorem	Theorem	Mathematical logic and foundations
Canonical bundle	Definition	Algebraic geometry
Lopatinskii–Shapiro condition	Definition	Partial differential equations
Regular chain	Definition	Commutative algebra
Deck transformation group	Concept	Manifolds and cell complexes
Prime-factor FFT algorithm	Theorem	Numerical analysis
Several complex variables	Concept	Several complex variables and analytic spaces
Caputo fractional derivative	Definition	Real functions
Symmetric spectrum	Definition	Algebraic topology
Percolation theory	Concept	Probability theory and stochastic processes
Upper bound theorem	Theorem	Convex and discrete geometry
Cyclotomic field	Definition	Number theory
Group von Neumann algebra	Definition	Topological groups, Lie groups
Multijet transversality theorem	Theorem	Manifolds and cell complexes
Outer measure	Concept	Measure and integration
Copula	Definition	Statistics
Divide-and-conquer eigenvalue algorithm	Theorem	Numerical analysis
Perfect ring	Definition	Associative rings and algebras
Asymptotic expansion	Concept	Approximations and expansions
Colimit	Concept	Category theory; homological algebra
Vietoris topology	Concept	General topology
Floquet theory	Concept	Ordinary differential equations
Euler class	Concept	Manifolds and cell complexes
Kleene algebra	Concept	Associative rings and algebras
Tate–Shafarevich group	Concept	Number theory
Spencer cohomology	Concept	Global analysis, analysis on manifolds
Multiplier ideal	Concept	Algebraic geometry
Dynamic equation on time scales	Concept	Ordinary differential equations
Spherical function	Concept	Abstract harmonic analysis
Langlands decomposition	Theorem	Topological groups, Lie groups
The cosets of 3Z in the integers	Example	Group theory and generalizations
Multivariate interpolation	Concept	Approximations and expansions
Prolongation of a section to a jet bundle	Concept	Global analysis, analysis on manifolds
Proof that the order of an element divides the order of the group	Proof	Group theory and generalizations
Regular singular point	Definition	Ordinary differential equations
Algebra of bounded operators on a Hilbert space	Object	Operator theory
Galois theory	Definition	Field theory and polynomials
Spectrum of an operator	Concept	Operator theory
Weakly singular kernel	Definition	Integral equations
Nyquist–Shannon sampling theorem	Theorem	Information and communication theory, circuits
Hankel inversion theorem	Theorem	Integral transforms, operational calculus
Submersion	Concept	Manifolds and cell complexes
Heyting algebra	Definition	Order, lattices, ordered algebraic structures
E8 manifold	Object	Manifolds and cell complexes
Smoothing spline	Concept	Numerical analysis
Hilbert–Samuel function	Concept	Commutative algebra
Braid group	Concept	Group theory and generalizations
Serre's vanishing theorem on affine schemes	Theorem	Algebraic geometry
Lattice homomorphism	Concept	Order, lattices, ordered algebraic structures
Hyperbolic 3-manifold	Definition	Manifolds and cell complexes
Oka's normalization theorem	Theorem	Several complex variables and analytic spaces
Følner condition	Definition	Abstract harmonic analysis
Frame operator	Concept	Harmonic analysis on Euclidean spaces
Convergence in measure	Definition	Measure and integration
Enriched category	Concept	Category theory; homological algebra
Matrix pencil	Definition	Linear and multilinear algebra; matrix theory
Galois insertion	Concept	Order, lattices, ordered algebraic structures
Interior operator	Definition	Order, lattices, ordered algebraic structures
Pol–Inv Galois connection	Theorem	General algebraic systems
Regularity structures	Concept	Probability theory and stochastic processes
Dahlquist barriers	Theorem	Numerical analysis
Generator	Definition	Category theory; homological algebra
Embedding of structures	Definition	General algebraic systems
Mean value theorem for divided differences	Theorem	Numerical analysis
Ramification group	Concept	Number theory
Newton–Cotes formulas	Concept	Numerical analysis
Term	Definition	Mathematical logic and foundations
Complex dynamics	Concept	Dynamical systems and ergodic theory
Algebra of sets	Definition	Measure and integration
Fano variety	Definition	Algebraic geometry
Blancmange curve	Example	Real functions
Minimal deviation property of Chebyshev polynomials	Theorem	Approximations and expansions
Hölder space	Definition	Functional analysis
Breakdown point	Concept	Statistics
Extraspecial group	Definition	Group theory and generalizations
Torelli theorem	Theorem	Algebraic geometry
Zimmer program	Concept	Dynamical systems and ergodic theory
Linear canonical transformation	Definition	Integral transforms, operational calculus
Embedding dimension	Definition	Commutative algebra
Duality in order theory	Definition	Order, lattices, ordered algebraic structures
Strong Cesàro summability	Definition	Sequences, series, summability
Random walk on a group	Definition	Probability theory and stochastic processes