Every idea

Ideas 6301–6450 of 7806.

Name	Kind	Subject
Riemann's existence theorem	Theorem	Functions of a complex variable
Dvoretzky's theorem	Theorem	Functional analysis
Hyperarithmetical theory	Concept	Mathematical logic and foundations
Torus knot	Concept	Manifolds and cell complexes
Completion of a ring	Definition	Commutative algebra
Symmetric function	Definition	Combinatorics
Kuratowski closure axioms	Concept	General topology
Hilbert transform	Concept	Integral transforms, operational calculus
Supermartingale	Concept	Probability theory and stochastic processes
Geodesic	Concept	Differential geometry
Commutative Gelfand–Naimark theorem	Theorem	Functional analysis
Resonance	Definition	Ordinary differential equations
Sierpiński space	Example	General topology
Cofinality	Definition	Mathematical logic and foundations
Specht module	Concept	Group theory and generalizations
Stopped process	Definition	Probability theory and stochastic processes
Švarc–Milnor lemma	Theorem	Group theory and generalizations
Fundamental group	Definition	Algebraic topology
Crossed product	Definition	Functional analysis
Brown–Peterson cohomology	Definition	Algebraic topology
Transcendence degree	Definition	Field theory and polynomials
Associated bundle	Concept	Algebraic topology
Inaccessible cardinal	Concept	Mathematical logic and foundations
Frobenius element	Definition	Number theory
Enumerative combinatorics	Definition	Combinatorics
Browder–Minty theorem	Theorem	Operator theory
Montel space	Concept	Functional analysis
Osculating circle	Concept	Differential geometry
Lefschetz duality	Theorem	Algebraic topology
Almost complex manifold	Definition	Differential geometry
Grothendieck inequality	Theorem	Functional analysis
Caristi fixed-point theorem	Theorem	Operator theory
Gaussian measure	Definition	Measure and integration
Real spectrum of self-adjoint operators	Theorem	Operator theory
Projective hierarchy	Definition	Mathematical logic and foundations
Closed operator	Definition	Operator theory
Complex measure	Concept	Measure and integration
de Branges space	Concept	Functional analysis
Adele ring	Definition	Number theory
Post's theorem	Theorem	Mathematical logic and foundations
Krein–Smulian theorem	Theorem	Functional analysis
Hyperfinite type II1 factor	Object	Functional analysis
Friedrichs extension	Definition	Operator theory
Matrix congruence	Definition	Linear and multilinear algebra; matrix theory
Symplectic integrator	Definition	Numerical analysis
Coupling from the past	Concept	Numerical analysis
Abelian differential	Concept	Functions of a complex variable
Gaussian measure	Concept	Measure and integration
Absolutely continuous measure	Concept	Measure and integration
Schwarz reflection principle	Theorem	Functions of a complex variable
Harnack's principle	Theorem	Potential theory
Measure space	Concept	Measure and integration
Character table	Concept	Group theory and generalizations
Higher-order logic	Concept	Mathematical logic and foundations
Hilbert's program	Problem	Mathematical logic and foundations
G2 manifold	Concept	Differential geometry
Additive combinatorics	Definition	Number theory
Nerve of a cover	Definition	Algebraic topology
Operator monotone function	Definition	Operator theory
Baire space of sequences	Object	General topology
Pseudo algebraically closed field	Definition	Field theory and polynomials
Elementary equivalence	Concept	Mathematical logic and foundations
Hankel operator	Concept	Operator theory
Tensor algebra	Concept	Linear and multilinear algebra; matrix theory
Surface	Definition	Manifolds and cell complexes
Kervaire invariant	Concept	Algebraic topology
Singular function	Concept	Real functions
Turing degree	Concept	Mathematical logic and foundations
Queueing theory	Concept	Probability theory and stochastic processes
Slice knot	Concept	Manifolds and cell complexes
Wirtinger presentation	Theorem	Manifolds and cell complexes
Weak topology	Concept	Functional analysis
Smooth four-dimensional Poincaré conjecture	Conjecture	Manifolds and cell complexes
Characterizations of Galois extensions	Theorem	Field theory and polynomials
Higman embedding theorem	Theorem	Group theory and generalizations
Group law on an elliptic curve	Concept	Algebraic geometry
Parallel transport	Definition	Differential geometry
Train track	Definition	Manifolds and cell complexes
Pitchfork bifurcation	Concept	Ordinary differential equations
Lorentz's characterization of almost convergence	Theorem	Sequences, series, summability
Local homomorphism	Concept	Commutative algebra
Positive operator	Definition	Operator theory
Nilpotent operator	Definition	Operator theory
Homotopy group	Concept	Algebraic topology
Group homology	Definition	Group theory and generalizations
S-finite measure	Concept	Measure and integration
Developable surface	Definition	Differential geometry
Turing reduction	Concept	Mathematical logic and foundations
Mean curvature	Concept	Differential geometry
Löwner's theorem	Theorem	Operator theory
Symmetric space	Concept	Differential geometry
Tucker's lemma	Lemma	Combinatorics
Laplace–Beltrami operator	Definition	Global analysis, analysis on manifolds
Symmetric function	Concept	Combinatorics
Combinatorial design	Concept	Combinatorics
Frobenius reciprocity	Theorem	Group theory and generalizations
Natural deduction	Definition	Mathematical logic and foundations
Minkowski functional	Concept	Functional analysis
Double series	Concept	Sequences, series, summability
Motzkin number	Concept	Combinatorics
Serre fibration	Concept	Algebraic topology
Symmetric algebra	Concept	Linear and multilinear algebra; matrix theory
Word problem for groups	Problem	Group theory and generalizations
Muirhead's inequality	Theorem	Real functions
Discrete spectrum	Definition	Operator theory
Choquet theory	Definition	Functional analysis
Recurrence and transience of states	Concept	Probability theory and stochastic processes
Multiplicative set	Definition	Commutative algebra
Sierpiński carpet	Example	General topology
Levi-Civita connection	Definition	Differential geometry
State on a C*-algebra	Definition	Functional analysis
Convergence of an infinite product	Concept	Sequences, series, summability
Commutative algebra over a ring	Definition	Commutative algebra
Residual set	Definition	General topology
CW approximation	Theorem	Algebraic topology
Laguerre–Pólya class	Definition	Functions of a complex variable
Bishop–Phelps theorem	Theorem	Functional analysis
Gateaux derivative	Definition	Functional analysis
Hedetniemi's conjecture	Counterexample	Combinatorics
Absolute summability	Definition	Sequences, series, summability
Torsion-free group	Concept	Group theory and generalizations
Axiom of determinacy	Concept	Mathematical logic and foundations
Content	Concept	Measure and integration
Algebra of sets	Concept	Measure and integration
Contraction semigroup	Definition	Operator theory
Homotopy group	Definition	Algebraic topology
Amenable group	Definition	Abstract harmonic analysis
Kneser's theorem on solution sets	Theorem	Ordinary differential equations
Quasicircle	Definition	Functions of a complex variable
Mahlo cardinal	Definition	Mathematical logic and foundations
Absolute Galois group	Concept	Field theory and polynomials
Motzkin number	Definition	Combinatorics
Hopfian group	Concept	Group theory and generalizations
Regular conditional probability	Concept	Probability theory and stochastic processes
Ax–Kochen theorem	Theorem	Field theory and polynomials
Measurable function	Definition	Measure and integration
Lie derivative	Concept	Differential geometry
Discrete spectrum	Concept	Operator theory
Hausdorff summation	Concept	Sequences, series, summability
Non-measurable set	Concept	Measure and integration
Sub-Gaussian distribution	Definition	Probability theory and stochastic processes
Petersen's theorem	Theorem	Combinatorics
q-derivative	Concept	Combinatorics
Littlewood subordination theorem	Theorem	Functions of a complex variable
Quasisymmetric map	Definition	Functions of a complex variable
Pentagonal number theorem	Theorem	Number theory
Noetherian module	Definition	Commutative algebra
Airy equation	Example	Ordinary differential equations
Strongly minimal theory	Concept	Mathematical logic and foundations
Hardy space	Concept	Functions of a complex variable