Every idea

Ideas 19351–19500 of 19934.

Name	Kind	Subject
Connes embedding problem	Problem	Functional analysis
Laplace's integral for Legendre polynomials	Theorem	Special functions
Thermodynamic stability conditions	Theorem	Classical thermodynamics, heat transfer
Rayleigh dissipation function	Concept	Mechanics of particles and systems
Morse index theorem for geodesics	Theorem	Global analysis, analysis on manifolds
Doodson numbers	Concept	Geophysics
Electric field	Concept	Optics, electromagnetic theory
Manifold with boundary	Definition	Manifolds and cell complexes
Lying over theorem	Theorem	Commutative algebra
Measure algebra	Concept	Measure and integration
Deceleration parameter	Definition	Relativity and gravitational theory
Symmetric algebra	Definition	Linear and multilinear algebra; matrix theory
Pochhammer symbol	Concept	Combinatorics
Magnetic reconnection	Concept	Fluid mechanics
Calabi–Yau manifold	Definition	Algebraic geometry
Periodicity equation	Concept	Difference and functional equations
t–J model	Example	Statistical mechanics, structure of matter
G-theory	Concept	K-theory
Field of formal Laurent series	Concept	Commutative algebra
Arity	Definition	General algebraic systems
Slice category	Definition	Category theory; homological algebra
Koszul complex	Concept	Commutative algebra
Kolmogorov–Smirnov test	Concept	Statistics
Schubert variety	Concept	Algebraic geometry
Self-concordant function	Definition	Operations research, mathematical programming
Semicontinuity	Definition	General topology
Phylogenetic network	Concept	Biology and other natural sciences
Sard–Smale theorem	Theorem	Global analysis, analysis on manifolds
Zel'dovich approximation	Definition	Astronomy and astrophysics
Chern–Simons form	Definition	Differential geometry
Supermanifold	Concept	Global analysis, analysis on manifolds
Proof that a bounded sequence converges iff its liminf and limsup agree	Proof	Sequences, series, summability
Line segment	Definition	Convex and discrete geometry
Lieb–Schultz–Mattis theorem	Theorem	Statistical mechanics, structure of matter
Uniserial module	Concept	Associative rings and algebras
Thin plate spline	Definition	Approximations and expansions
Earth's magnetic field	Concept	Geophysics
Order filter	Concept	Order, lattices, ordered algebraic structures
Duality in category theory	Definition	Category theory; homological algebra
Racah polynomials	Definition	Special functions
Cotangent space of a local ring	Concept	Commutative algebra
Ruin theory	Definition	Game theory, economics, finance, and other social and behavioral sciences
Difference algebra	Concept	Field theory and polynomials
Abel summation	Definition	Sequences, series, summability
Subharmonic function	Concept	Potential theory
Magnetic vector potential	Definition	Optics, electromagnetic theory
Hawking radiation	Theorem	Relativity and gravitational theory
Frobenius group	Definition	Group theory and generalizations
Lieb–Liniger integral equation	Example	Statistical mechanics, structure of matter
Operator exponential and translation	Proposition	Integral transforms, operational calculus
CR function	Definition	Several complex variables and analytic spaces
Axiom A	Concept	Dynamical systems and ergodic theory
Maximal torus	Definition	Topological groups, Lie groups
Prandtl stress function	Concept	Mechanics of deformable solids
Trace class operator	Concept	Operator theory
Principle of maximum entropy	Theorem	Information and communication theory, circuits
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
Suslin rigidity theorem	Theorem	K-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
von Neumann's theory of almost periodic functions on groups	Theorem	Abstract harmonic analysis
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
Current algebra	Concept	Nonassociative rings and algebras
Myers–Steenrod theorem	Theorem	Differential geometry
Cubic Hermite spline	Definition	Approximations and expansions
Exact category in the sense of Barr	Definition	Category theory; homological algebra
Beta reduction	Definition	Mathematical logic and foundations
Hairy ball theorem	Theorem	Manifolds and cell complexes
L-theory	Definition	K-theory
Stein space	Concept	Several complex variables and analytic spaces
Thermodynamic cycle	Definition	Classical thermodynamics, heat transfer
Lattice (group)	Definition	Number theory
Summation of families over arbitrary index sets	Definition	Sequences, series, summability
Bass conjecture	Conjecture	K-theory
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
Anderson–Kadec theorem	Theorem	Manifolds and cell complexes
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
Metabolic control analysis	Concept	Biology and other natural sciences
3-manifold	Definition	Manifolds and cell complexes
Bullen parameter	Definition	Geophysics
Zonotope	Concept	Convex and discrete geometry
Proper cone	Concept	Convex and discrete geometry
Bernstein–Bézier form	Concept	Approximations and expansions
Dévissage	Theorem	K-theory
Asymptotic expansion from poles of a Mellin transform	Definition	Integral transforms, operational calculus
Absolute stability problem of Lur'e	Problem	Systems theory; control
Thermal efficiency	Concept	Classical thermodynamics, heat transfer
Lomb–Scargle periodogram	Definition	Statistics
Lebesgue measure as Haar measure	Example	Abstract harmonic analysis
Heisenberg picture	Definition	Quantum theory
Complete elliptic integral of the first kind	Definition	Special functions
No-retraction theorem	Theorem	Algebraic topology
Fisher–Neyman factorization theorem	Theorem	Statistics
Komar mass	Definition	Relativity and gravitational theory
Goldreich–Tremaine theory of disk–satellite interaction	Definition	Astronomy and astrophysics
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
Scaling relations among critical exponents	Proposition	Statistical mechanics, structure of matter
Triebel–Lizorkin space	Definition	Functional analysis
Atiyah–Hirzebruch spectral sequence	Theorem	Algebraic topology
Massey product	Concept	Algebraic topology
Girsanov theorem	Theorem	Probability theory and stochastic processes
Zolotarev polynomials	Definition	Approximations and expansions
World line	Concept	Relativity and gravitational theory
Wheeler–DeWitt equation	Definition	Relativity and gravitational theory
Thomson scattering	Concept	Optics, electromagnetic theory
Spectral theory of dynamical systems	Concept	Dynamical systems and ergodic theory
Real analytic manifold	Concept	Several complex variables and analytic spaces
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
Strongly pseudoconvex domain	Concept	Several complex variables and analytic spaces
Optical transfer function	Concept	Optics, electromagnetic theory
Nyquist plot	Concept	Systems theory; control
Data envelopment analysis	Concept	Operations research, mathematical programming
Polar space	Concept	Geometry
Hunt process	Concept	Probability theory and stochastic processes