Every idea

Ideas 11701–11850 of 11985.

Name	Kind	Subject
Frobenius group	Definition	Group theory and generalizations
Axiom A	Concept	Dynamical systems and ergodic theory
Maximal torus	Definition	Topological groups, Lie groups
Trace class operator	Concept	Operator theory
Horner's method	Definition	Computer science
Parabolic subgroup	Concept	Topological groups, Lie groups
Lumer–Phillips theorem	Theorem	Operator theory
Morrey's inequality	Theorem	Functional analysis
Trace operator	Concept	Functional analysis
Hadamard product	Definition	Linear and multilinear algebra; matrix theory
Osculating circle	Definition	Differential geometry
Positive cone	Concept	Functional analysis
Littlewood's Tauberian theorem	Theorem	Sequences, series, summability
Lattice in a Lie group	Definition	Topological groups, Lie groups
Spectrum	Definition	Algebraic topology
Plane curve	Definition	Algebraic geometry
Inverse tangent integral	Definition	Special functions
Weierstrass equation	Concept	Algebraic geometry
Algebraic logic	Concept	Mathematical logic and foundations
Aperiodic set of prototiles	Concept	Convex and discrete geometry
Henselian field	Definition	Field theory and polynomials
Pushout	Definition	Category theory; homological algebra
Myers–Steenrod theorem	Theorem	Differential geometry
Exact category in the sense of Barr	Definition	Category theory; homological algebra
Hairy ball theorem	Theorem	Manifolds and cell complexes
Lattice (group)	Definition	Number theory
Summation of families over arbitrary index sets	Definition	Sequences, series, summability
Condensed set	Definition	Category theory; homological algebra
Little q-Jacobi polynomials	Concept	Special functions
Character of a representation	Definition	Group theory and generalizations
O'Nan–Scott theorem	Theorem	Group theory and generalizations
Whittaker–Shannon interpolation formula	Theorem	Information and communication theory, circuits
Abstract Wiener space	Definition	Measure and integration
Primitive ideal	Definition	Associative rings and algebras
Doob martingale	Example	Probability theory and stochastic processes
Band matrix	Concept	Linear and multilinear algebra; matrix theory
Oracle machine	Concept	Mathematical logic and foundations
Relatively complemented lattice	Definition	Order, lattices, ordered algebraic structures
Duality in category theory	Concept	Category theory; homological algebra
Projective morphism	Concept	Algebraic geometry
Chudnovsky algorithm	Definition	Number theory
Change detection	Problem	Statistics
3-manifold	Definition	Manifolds and cell complexes
Zonotope	Concept	Convex and discrete geometry
Proper cone	Concept	Convex and discrete geometry
Complete elliptic integral of the first kind	Definition	Special functions
No-retraction theorem	Theorem	Algebraic topology
Fisher–Neyman factorization theorem	Theorem	Statistics
Current	Definition	Calculus of variations and optimal control; optimization
Four-vertex theorem	Theorem	Differential geometry
Normal Moore space problem	Problem	General topology
Locally compact abelian group	Definition	Topological groups, Lie groups
Inherently nonfinitely based algebra	Concept	General algebraic systems
Triebel–Lizorkin space	Definition	Functional analysis
Massey product	Concept	Algebraic topology
Girsanov theorem	Theorem	Probability theory and stochastic processes
Spectral theory of dynamical systems	Concept	Dynamical systems and ergodic theory
Monomial ideal	Definition	Commutative algebra
Interior operator	Concept	Order, lattices, ordered algebraic structures
Solvable by radicals	Definition	Field theory and polynomials
Golden–Thompson inequality	Theorem	Linear and multilinear algebra; matrix theory
Sard's theorem	Theorem	Global analysis, analysis on manifolds
Successor order	Definition	Order, lattices, ordered algebraic structures
Polar space	Concept	Geometry
Undecidability of the halting problem	Theorem	Mathematical logic and foundations
Curve-shortening flow	Definition	Differential geometry
Tensor decomposition	Definition	Linear and multilinear algebra; matrix theory
Word problem for free lattices	Theorem	Order, lattices, ordered algebraic structures
Stone–von Neumann theorem	Theorem	Topological groups, Lie groups
Essentially self-adjoint operator	Definition	Operator theory
Euler integral for the gamma function	Theorem	Special functions
Finite-rank operator	Concept	Operator theory
Synge's theorem	Theorem	Differential geometry
Monogenic function	Definition	Functions of a complex variable
Fourier series of Bernoulli polynomials	Example	Harmonic analysis on Euclidean spaces
Martin's axiom	Definition	Mathematical logic and foundations
Christoffel symbols	Definition	Differential geometry
Congruence lattice	Definition	General algebraic systems
Reeb stability theorem	Theorem	Manifolds and cell complexes
Kervaire invariant problem	Problem	Algebraic topology
Weil divisor	Concept	Algebraic geometry
Topological manifold	Definition	Manifolds and cell complexes
Flag variety	Definition	Algebraic geometry
Prime ring	Concept	Associative rings and algebras
Symbol class	Definition	Partial differential equations
Hurewicz theorem	Theorem	Algebraic topology
Dehn surgery	Concept	Manifolds and cell complexes
CSP dichotomy theorem	Theorem	General algebraic systems
Singular perturbation	Definition	Ordinary differential equations
Curvature form	Concept	Differential geometry
Well-founded order	Definition	Order, lattices, ordered algebraic structures
Allen–Cahn equation	Definition	Partial differential equations
Moment map	Concept	Differential geometry
Linear discriminant analysis	Concept	Statistics
Steiner conic	Definition	Geometry
First and second variation of arc length	Theorem	Differential geometry
Gowers norm	Concept	Number theory
Theta correspondence	Concept	Number theory
Fundamental groupoid	Concept	Algebraic topology
Category of posets	Concept	Category theory; homological algebra
Cauchy's functional equation	Problem	Difference and functional equations
Cartan matrix of an algebra	Concept	Associative rings and algebras
Bernstein's theorem on monotone functions	Theorem	Real functions
Fuchsian equation	Concept	Ordinary differential equations
Hirsch conjecture	Counterexample	Convex and discrete geometry
Littlewood–Paley square function	Definition	Harmonic analysis on Euclidean spaces
Quadratic variation	Definition	Probability theory and stochastic processes
Normal form	Definition	Ordinary differential equations
Universal bundle	Definition	Algebraic topology
Beth number	Definition	Mathematical logic and foundations
Lawson topology	Concept	Order, lattices, ordered algebraic structures
Functional equation of the gamma function	Theorem	Special functions
Hermite equation	Example	Ordinary differential equations
Alexandrov's theorem on polyhedra	Theorem	Convex and discrete geometry
Regular cardinal	Definition	Mathematical logic and foundations
Mathieu function	Definition	Special functions
Amenable group action	Concept	Abstract harmonic analysis
Varifold	Definition	Calculus of variations and optimal control; optimization
Minimum-variance unbiased estimator	Concept	Statistics
Immersion	Definition	Manifolds and cell complexes
Concrete category of algebras	Concept	General algebraic systems
Primary decomposition	Concept	Commutative algebra
Birational map	Definition	Algebraic geometry
Barratt–Priddy–Quillen theorem	Theorem	Algebraic topology
Sklar's theorem	Theorem	Statistics
Blocking set	Concept	Geometry
Ehrhart–Macdonald reciprocity	Theorem	Convex and discrete geometry
Semilocal ring	Concept	Associative rings and algebras
Permutation group	Concept	Group theory and generalizations
Continuous lattice	Definition	Order, lattices, ordered algebraic structures
Colombeau algebra	Definition	Functional analysis
Barrelled space	Concept	Functional analysis
Anti-equivalence of affine schemes and rings	Theorem	Algebraic geometry
Fundamental class	Concept	Manifolds and cell complexes
Join	Concept	General topology
Support of a measure	Definition	Measure and integration
Many-sorted algebra	Definition	General algebraic systems
Irreducible matrix	Definition	Linear and multilinear algebra; matrix theory
Variogram	Concept	Statistics
Dirac operator	Definition	Global analysis, analysis on manifolds
Δ-complex	Concept	Algebraic topology
Fundamental groupoid	Definition	Algebraic topology
Kirby calculus	Definition	Manifolds and cell complexes
Lyapunov equation	Definition	Linear and multilinear algebra; matrix theory
Functor category	Definition	Category theory; homological algebra
Black–Scholes equation	Concept	Partial differential equations
Normed field	Concept	Field theory and polynomials
Quasi-isometry	Definition	Group theory and generalizations
Priestley space	Concept	Order, lattices, ordered algebraic structures
Flexible polyhedron	Example	Convex and discrete geometry