Every idea

Ideas 6451–6600 of 14183.

Name	Kind	Subject
Discrete valuation	Concept	Field theory and polynomials
Poisson manifold	Concept	Differential geometry
Crisis	Definition	Dynamical systems and ergodic theory
Transversality	Concept	Manifolds and cell complexes
Mellin convolution	Concept	Integral transforms, operational calculus
Comb space	Counterexample	General topology
Failure of Aizerman's conjecture	Counterexample	Systems theory; control
CR manifold	Definition	Several complex variables and analytic spaces
Backward error analysis	Definition	Numerical analysis
Germ of an analytic set	Definition	Several complex variables and analytic spaces
Homotopy limit	Definition	Category theory; homological algebra
Dandelin spheres	Definition	Geometry
Multiple gamma function	Definition	Special functions
Monge–Ampère equation	Definition	Partial differential equations
Topological homogeneity	Concept	General topology
Clifford algebra	Concept	Linear and multilinear algebra; matrix theory
Real form of a Lie group	Definition	Topological groups, Lie groups
Proj construction	Concept	Algebraic geometry
Hopf invariant one problem	Theorem	Algebraic topology
Linear topology	Definition	Commutative algebra
Generalized minimal residual method	Theorem	Numerical analysis
Blichfeldt's theorem	Theorem	Number theory
Runge domain	Concept	Several complex variables and analytic spaces
Lebesgue covering dimension	Concept	General topology
Tate cohomology	Definition	Group theory and generalizations
Disjoint union topology	Definition	General topology
Ordered group	Definition	Order, lattices, ordered algebraic structures
Skeleton of a category	Concept	Category theory; homological algebra
Hausdorff topological group	Definition	Topological groups, Lie groups
Almgren–Pitts min-max theory	Definition	Global analysis, analysis on manifolds
Projective variety	Concept	Algebraic geometry
Prolongation of a section to a jet bundle	Definition	Global analysis, analysis on manifolds
Moduli space	Definition	Algebraic geometry
Multiplication formula for the Fourier transform	Proposition	Harmonic analysis on Euclidean spaces
Cusp form	Concept	Number theory
Brelot space	Concept	Potential theory
Uniform space	Concept	General topology
Gauss–Lucas theorem	Theorem	Real functions
Tautochrone problem	Problem	Integral equations
Frullani integral	Theorem	Real functions
Conditionally complete lattice	Definition	Order, lattices, ordered algebraic structures
Shock wave	Definition	Partial differential equations
Ideal completion	Concept	Order, lattices, ordered algebraic structures
Cartan decomposition of a Lie group	Theorem	Topological groups, Lie groups
Discrete-time dynamical system	Definition	Dynamical systems and ergodic theory
Minimum total potential energy principle	Theorem	Mechanics of deformable solids
Dirac operator on a spin manifold	Definition	Differential geometry
Fourier transform on locally compact abelian groups	Definition	Abstract harmonic analysis
Arc in a finite plane	Definition	Geometry
Birkhoff's axioms	Definition	Geometry
Collar neighbourhood theorem	Theorem	Manifolds and cell complexes
Continuous-time Markov chain	Definition	Probability theory and stochastic processes
Directional statistics	Definition	Statistics
Ultrametric space	Concept	General topology
Irregular singularity	Definition	Ordinary differential equations
Marden's theorem	Theorem	Functions of a complex variable
Distinguished boundary of a polydisc	Concept	Several complex variables and analytic spaces
Term rewriting for equational theories	Concept	Computer science
Pythagorean field	Concept	Field theory and polynomials
Trigonometric polynomial	Definition	Harmonic analysis on Euclidean spaces
James–Stein estimator	Definition	Statistics
Core model	Concept	Mathematical logic and foundations
Selmer group	Definition	Number theory
Shift space	Definition	Dynamical systems and ergodic theory
Kurosh–Amitsur radical theory	Concept	Associative rings and algebras
Schur-convex function	Concept	Real functions
Darboux function	Definition	Real functions
Melnikov method	Concept	Ordinary differential equations
Signature operator	Definition	Global analysis, analysis on manifolds
Curry–Howard correspondence	Concept	Mathematical logic and foundations
Modulus of continuity	Definition	Real functions
Gauss's test	Theorem	Sequences, series, summability
Persistent homology	Definition	Algebraic topology
Multidimensional Z-transform	Concept	Integral transforms, operational calculus
Fractional Sobolev space	Definition	Functional analysis
Infinite loop space	Concept	Algebraic topology
Grothendieck category	Concept	Category theory; homological algebra
Newtonian kernel	Definition	Potential theory
Bounded variation	Concept	Real functions
Virtual knot	Definition	Manifolds and cell complexes
Absolute summability	Concept	Sequences, series, summability
Mittag-Leffler summation	Definition	Sequences, series, summability
Determinant trick	Lemma	Commutative algebra
Nijenhuis tensor	Definition	Differential geometry
Ideal of compact operators	Definition	Operator theory
Mortar methods	Definition	Numerical analysis
Symplectomorphism	Concept	Differential geometry
Separable algebra	Definition	Associative rings and algebras
Numerical integration	Definition	Numerical analysis
Van Wijngaarden transformation	Definition	Numerical analysis
Heine's transformation	Theorem	Special functions
Second fundamental form	Definition	Differential geometry
Order polytope	Definition	Order, lattices, ordered algebraic structures
Coxeter group	Definition	Group theory and generalizations
Rectangular function	Example	Harmonic analysis on Euclidean spaces
Packing density	Definition	Convex and discrete geometry
Banach limit	Definition	Sequences, series, summability
Quasiconformal mapping	Definition	Functions of a complex variable
Thom–Boardman singularities	Concept	Manifolds and cell complexes
Controllability	Concept	Systems theory; control
Littlewood–Paley theory	Concept	Harmonic analysis on Euclidean spaces
Linear difference equation	Concept	Difference and functional equations
Class field theory	Definition	Number theory
Geometry of numbers	Concept	Number theory
Laplacian eigenvalues of the round sphere	Example	Global analysis, analysis on manifolds
Primitive permutation group	Definition	Group theory and generalizations
Fourier series on the torus	Concept	Harmonic analysis on Euclidean spaces
Legendre functions	Definition	Special functions
Kriging	Definition	Statistics
Regular conditional probability	Definition	Probability theory and stochastic processes
du Bois-Reymond lemma	Lemma	Calculus of variations and optimal control; optimization
Presentation of an algebra	Definition	General algebraic systems
The subgroups of the symmetric group S4	Computation
Tarski's finite basis problem	Problem	General algebraic systems
Log-convexity of the gamma function	Theorem	Special functions
Condition number	Concept	Linear and multilinear algebra; matrix theory
Singular integral equation	Definition	Integral equations
Theorem of the three geodesics	Theorem	Differential geometry
Lie sphere geometry	Definition	Geometry
Standard Borel space	Concept	Measure and integration
Dunkl operator	Definition	Special functions
Quotient of a topological group	Definition	Topological groups, Lie groups
Cantor's isomorphism theorem	Theorem	Order, lattices, ordered algebraic structures
Choquet theory	Concept	Functional analysis
Atkinson's theorem	Theorem	Operator theory
Quasi-Monte Carlo method	Concept	Numerical analysis
Gluing of schemes	Concept	Algebraic geometry
Principal component analysis	Concept	Statistics
Smith conjecture	Theorem	Manifolds and cell complexes
Landau's constants	Concept	Functions of a complex variable
Kantorovich duality	Theorem	Calculus of variations and optimal control; optimization
Finite type algebra	Concept	Commutative algebra
Yamabe flow	Concept	Differential geometry
Multigrid method	Theorem	Numerical analysis
Summability kernel	Definition	Harmonic analysis on Euclidean spaces
GCD domain	Concept	Commutative algebra
Bogdanov–Takens bifurcation	Concept	Ordinary differential equations
Sinai's factor theorem	Theorem	Dynamical systems and ergodic theory
Weierstrass product	Concept	Functions of a complex variable
Pompeiu derivative	Example	Real functions
Polynomially convex set	Concept	Several complex variables and analytic spaces
Green–Griffiths–Lang conjecture	Conjecture	Several complex variables and analytic spaces
Linear multistep method	Definition	Numerical analysis
Toda lattice	Example	Dynamical systems and ergodic theory
Relative homotopy	Concept	Algebraic topology
Birkhoff polytope	Example	Convex and discrete geometry
Fredholm index	Definition	Operator theory
3-j symbol	Definition	Special functions
Distinguished triangle	Concept	Category theory; homological algebra
Tautological one-form	Concept	Differential geometry