Every idea

Ideas 21451–21600 of 21839.

Name	Kind	Subject
Universal bundle	Definition	Algebraic topology
Much-greater-or-less	Concept
Principle of virtual work	Theorem	Mechanics of particles and systems
Beth number	Definition	Mathematical logic and foundations
Travel-time curve	Definition	Geophysics
Spacetime	Definition	Relativity and gravitational theory
CR manifold	Concept	Several complex variables and analytic spaces
Lawson topology	Concept	Order, lattices, ordered algebraic structures
Functional equation of the gamma function	Theorem	Special functions
Moishezon manifold	Definition	Several complex variables and analytic spaces
Product formula for the totient function	Theorem	Number theory
Nonlinear Schrödinger equation in optics	Definition	Optics, electromagnetic theory
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
Global optimization	Concept	Operations research, mathematical programming
Amenable group action	Concept	Abstract harmonic analysis
Karp's 21 NP-complete problems	Example	Computer science
Infinitesimal strain theory	Definition	Mechanics of deformable solids
Varifold	Definition	Calculus of variations and optimal control; optimization
Minimum-variance unbiased estimator	Concept	Statistics
Microcanonical ensemble	Definition	Statistical mechanics, structure of matter
Top trading cycle	Concept	Game theory, economics, finance, and other social and behavioral sciences
Boolean network	Definition	Biology and other natural sciences
Lagrange basis polynomials	Definition	Approximations and expansions
Immersion	Definition	Manifolds and cell complexes
Constructive set theory	Concept
Division with remainder for natural numbers	Theorem	Number theory
Concrete category of algebras	Concept	General algebraic systems
Non-deterministic polynomial time	Concept
Roche lobe	Definition	Mechanics of particles and systems
Primary decomposition	Concept	Commutative algebra
Strength (mathematical logic)	Concept
Birational map	Definition	Algebraic geometry
Barratt–Priddy–Quillen theorem	Theorem	Algebraic topology
Sklar's theorem	Theorem	Statistics
Blocking set	Concept	Geometry
Proof of the existence of an algebraic closure	Proof	Field theory and polynomials
Ehrhart–Macdonald reciprocity	Theorem	Convex and discrete geometry
Bareiss algorithm	Theorem	Numerical analysis
Semilocal ring	Concept	Associative rings and algebras
Manifold of smooth mappings	Definition	Global analysis, analysis on manifolds
Kolmogorov microscales	Definition	Fluid mechanics
Harmonic majorant	Concept	Potential theory
Iterative conception of set	Concept
Permutation group	Concept	Group theory and generalizations
Continuous lattice	Definition	Order, lattices, ordered algebraic structures
Integral equation of the first kind	Concept	Integral equations
Fluid dynamics	Definition	Fluid mechanics
Colombeau algebra	Definition	Functional analysis
Spin factor	Example	Nonassociative rings and algebras
Potential of a measure	Definition	Potential theory
Tikhonov regularization	Definition	Operator theory
Linearity of the matrix-vector product	Proposition	Linear and multilinear algebra; matrix theory
Hartley transform	Definition	Integral transforms, operational calculus
Isothermal process	Definition	Classical thermodynamics, heat transfer
Barrelled space	Concept	Functional analysis
Anti-equivalence of affine schemes and rings	Theorem	Algebraic geometry
Fundamental class	Concept	Manifolds and cell complexes
Smirnov's theorem on conformal invariance of percolation	Theorem	Statistical mechanics, structure of matter
Join	Concept	General topology
E-theory	Definition	K-theory
Haldane conjecture	Conjecture	Statistical mechanics, structure of matter
Ocean wave spectrum	Definition	Geophysics
Support of a measure	Definition	Measure and integration
Method of images	Definition	Potential theory
Hartogs lemma for subharmonic functions	Lemma	Potential theory
Many-sorted algebra	Definition	General algebraic systems
Cosmological principle	Definition	Relativity and gravitational theory
Irreducible matrix	Definition	Linear and multilinear algebra; matrix theory
Proof that the closure is the set of limits of sequences	Proof	General topology
Haar measure on the circle	Example	Abstract harmonic analysis
Variogram	Concept	Statistics
Dirac operator	Definition	Global analysis, analysis on manifolds
Δ-complex	Concept	Algebraic topology
BCM theory	Definition	Biology and other natural sciences
Fundamental groupoid	Definition	Algebraic topology
Stochastic game	Definition	Game theory, economics, finance, and other social and behavioral sciences
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
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
Proof of continuity via open sets in metric spaces	Proof	General topology
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
Counterfactual logic	Concept
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
Proof of the universal property of the quotient ring	Proof	Associative rings and algebras
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
Proof that the Cantor set is closed	Proof	General topology
Count of integers up to n divisible by a set of primes dividing n	Proposition	Number theory
Hex theorem that the first player wins	Theorem	Game theory, economics, finance, and other social and behavioral sciences
Proof of the inscribed angle theorem by complex numbers	Proof	Geometry
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
Proof that continuous functions are Riemann integrable	Proof	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