Every idea

Ideas 19651–19800 of 19934.

Name	Kind	Subject
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
Hicksian demand function	Concept	Game theory, economics, finance, and other social and behavioral sciences
Strain rate tensor	Definition	Fluid mechanics
Quasi-isometry	Definition	Group theory and generalizations
Boussinesq approximation for buoyancy	Definition	Fluid mechanics
Priestley space	Concept	Order, lattices, ordered algebraic structures
Three-moment equation	Theorem	Mechanics of deformable solids
Flexible polyhedron	Example	Convex and discrete geometry
Turbo code	Definition	Information and communication theory, circuits
Faber polynomials	Definition	Functions of a complex variable
Orlicz space	Definition	Functional analysis
Soret effect	Concept	Classical thermodynamics, heat transfer
Parallelizable manifold	Definition	Manifolds and cell complexes
Homotopy K-theory	Definition	K-theory
Plate reconstruction	Concept	Geophysics
Killing horizon	Definition	Relativity and gravitational theory
Markov chain Monte Carlo	Concept	Numerical analysis
Distributed parameter system	Definition	Systems theory; control
Symplectic Lie algebra	Example	Nonassociative rings and algebras
Trilateration	Definition	Geophysics
K-theory spectrum	Definition	K-theory
Complementary error function	Definition	Special functions
Held–Karp algorithm	Definition	Operations research, mathematical programming
Deligne–Lusztig theory	Concept	Group theory and generalizations
Paracompact space	Definition	General topology
Oscillation theory	Concept	Ordinary differential equations
Graceful tree conjecture	Conjecture	Combinatorics
Syndrome decoding	Concept	Information and communication theory, circuits
Ciphertext indistinguishability	Concept	Information and communication theory, circuits
Green's function	Definition	Ordinary differential equations
Smooth morphism of rings	Definition	Commutative algebra
Relative homotopy group	Concept	Algebraic topology
Hyperelastic material	Concept	Mechanics of deformable solids
Pesin theory	Concept	Dynamical systems and ergodic theory
Globally hyperbolic spacetime	Definition	Differential geometry
Transonic small disturbance equation	Concept	Fluid mechanics
Join-irreducible element	Concept	Order, lattices, ordered algebraic structures
Scalar curvature	Concept	Differential geometry
Domain of finite type	Concept	Several complex variables and analytic spaces
Hex theorem that the first player wins	Theorem	Game theory, economics, finance, and other social and behavioral sciences
Quasigroup	Concept	Group theory and generalizations
Weighted polynomial approximation	Definition	Approximations and expansions
C0-semigroup	Definition	Operator theory
Optical theorem	Theorem	Optics, electromagnetic theory
Inviscid flow	Concept	Fluid mechanics
Quantum decoherence	Definition	Quantum theory
Banach–Mazur distance	Concept	Functional analysis
Gomory's fractional cut	Definition	Operations research, mathematical programming
Cone theorem	Theorem	Algebraic geometry
Adams' theorem on Hopf invariant one	Theorem	Algebraic topology
Concave up and concave down	Concept	Real functions
Generalized Boolean algebra	Concept	Order, lattices, ordered algebraic structures
Laplace transform of a periodic function	Example	Integral transforms, operational calculus
Moyal product	Definition	Differential geometry
Jacobi identity	Proposition	Nonassociative rings and algebras
Levi pseudoconvex domain	Definition	Several complex variables and analytic spaces
Weber number	Concept	Fluid mechanics
Holomorphy of the gamma function	Theorem	Special functions
Enflo's counterexample to the approximation problem	Counterexample	Functional analysis
Lindley equation	Definition	Probability theory and stochastic processes
Sheaf of differentials	Definition	Algebraic geometry
Cascade algorithm	Definition	Numerical analysis
Laplace tidal equations	Definition	Geophysics
Residual bound conjecture	Conjecture	General algebraic systems
Continuous kernel	Concept	Integral equations
Mellin transform under inversion of the variable	Proposition	Integral transforms, operational calculus
Frenet–Serret formulas	Theorem	Differential geometry
Hilbert–Schmidt integral operator	Definition	Operator theory
Functional differential equation	Concept	Ordinary differential equations
Chevalley group	Definition	Group theory and generalizations
Banach–Zarecki theorem	Theorem	Real functions
Cauchy–Green deformation tensor	Definition	Mechanics of deformable solids
Griess algebra	Object	Group theory and generalizations
Laser rate equations	Concept	Optics, electromagnetic theory
Bieberbach conjecture	Theorem	Functions of a complex variable
Runge's phenomenon	Example	Approximations and expansions
Multi-commodity flow problem	Problem	Operations research, mathematical programming
Nest algebra	Concept	Operator theory
Representative elementary volume	Concept	Mechanics of deformable solids
Zonoid	Concept	Convex and discrete geometry
Fictitious force	Concept	Mechanics of particles and systems
Discrete Laplace operator	Concept	Difference and functional equations
Ramanujan's master theorem	Theorem	Integral transforms, operational calculus
Doob's h-transform	Concept	Probability theory and stochastic processes
Scattering parameters	Definition	Information and communication theory, circuits
Kontorovich–Lebedev transform	Definition	Integral transforms, operational calculus
Grauert's direct image theorem	Theorem	Several complex variables and analytic spaces
Hilbert transform of sinusoids	Example	Integral transforms, operational calculus
Fourier transform of the Gaussian	Proposition	Harmonic analysis on Euclidean spaces
Finite-dimensional Hausdorff vector topologies are Euclidean	Theorem	Functional analysis
Moment tensor	Concept	Geophysics
Hofstadter sequences	Example	Number theory
Representation of a Lie algebra	Definition	Nonassociative rings and algebras
Hartmann number	Concept	Fluid mechanics
Radical of an ideal	Definition	Commutative algebra
Sample mean and sample covariance	Concept	Statistics
Volume conjecture	Conjecture	Manifolds and cell complexes
Uniform algebra	Concept	Functional analysis
Representation ring	Definition	K-theory
Subtyping	Concept	Computer science
Carathéodory's royal road	Definition	Calculus of variations and optimal control; optimization
Landauer's principle	Fact	Statistical mechanics, structure of matter
Stochastic approximation	Concept	Statistics
Control system	Concept	Systems theory; control
Kazhdan–Lusztig conjecture	Theorem	Nonassociative rings and algebras
Waldhausen S-construction	Concept	Category theory; homological algebra
Bra–ket notation	Concept	Quantum theory
Observed information	Definition	Statistics
Generalized method of moments	Concept	Statistics
Irreducible component	Definition	Algebraic geometry
Conjugate points	Concept	Differential geometry
Lapse rate	Concept	Geophysics
Switched system	Definition	Systems theory; control
Enumerative geometry	Concept	Algebraic geometry
WKB approximation in optics	Concept	Optics, electromagnetic theory
Quantum inverse scattering method	Concept	Quantum theory
Proof that an intersection of subspaces is a subspace	Proof	Linear and multilinear algebra; matrix theory
Jacobian variety	Concept	Algebraic geometry
Progenerator	Concept	Associative rings and algebras
Fourier multiplier	Concept	Harmonic analysis on Euclidean spaces
Hardy–Littlewood circle method	Concept	Number theory
Skolem–Mahler–Lech theorem	Theorem	Number theory
Pauli exclusion principle	Proposition	Quantum theory
Propagation of uncertainty	Definition	Numerical analysis
Voronoi cell	Definition	Convex and discrete geometry
Kruskal's algorithm	Definition	Combinatorics
Donaldson theory	Concept	Manifolds and cell complexes
Legendre transformation	Concept	Real functions
Locally compact abelian group	Concept	Topological groups, Lie groups
Total variation diminishing scheme	Definition	Numerical analysis
Whitney–Graustein theorem	Theorem	Manifolds and cell complexes
Drazin inverse	Definition	Linear and multilinear algebra; matrix theory
Geomagnetic reversal	Concept	Geophysics
Łoś–Vaught test	Theorem	Mathematical logic and foundations
Scott topology	Concept	Order, lattices, ordered algebraic structures
Yarkovsky effect	Fact	Mechanics of particles and systems
Laws of thermodynamics	Fact	Classical thermodynamics, heat transfer
Feller process	Definition	Probability theory and stochastic processes
Semiperfect ring	Concept	Associative rings and algebras
Dialectica interpretation	Definition	Mathematical logic and foundations
Mirror descent	Concept	Operations research, mathematical programming
Crystal plasticity	Definition	Mechanics of deformable solids
Holomorphically convex domain	Definition	Several complex variables and analytic spaces
Bochner's theorem	Theorem	Abstract harmonic analysis
Point estimation	Definition	Statistics
Jacobi condition	Theorem	Calculus of variations and optimal control; optimization
Support of a convolution	Proposition	Integral transforms, operational calculus