Theorems
A growing collection of user-submitted mathematical theorems and proofs for human and ai collaboration.
- Let and be metric spaces and let be a nonnegative real number. A map is Lipschitz with constant if and Lipschitz if it is Lipschitz with constant…
Below-Frontier Evaluations, Tilted Poisson Moment Functions, and Multi-Base Window Bounds for Jointly Driven Solutions of the Controlled N-Agent Dynamics
lemmalem:n-agent-multibase-window-2026bProbabilityAdopt the setting, notation, and hypotheses of Level-Revealed Conditioning for Jointly Driven Solutions of the Controlled N-Agent Dynamics --- in particular the -algebra and the independence of the finite family consisting of together with…Interior Points in the Metric Topology are Exactly the Centres of Contained Closed Balls
lemmalem:interior-metric-closed-ball-criterion-2026aAnalysisTopologyLet be a metric space and let be the collection of the subsets of that are open in the metric space ; by Metric Open Sets Form a Topology the pair is a topological space, and interiors below are taken in it, in the sense…A Convex Function is Continuous near an Interior Point
corollarycor:convex-function-continuous-near-interior-point-2026aAnalysisMultivariable CalculusLet , , , , the Euclidean norm , the Euclidean metric and the closed balls of Closed Ball in a Metric Space be as in A Convex Function is Lipschitz on a Ball around an Interior Point. Regard…A Convex Function is Lipschitz on a Ball around an Interior Point
theoremthm:convex-function-lipschitz-near-interior-point-2026aAnalysisMultivariable CalculusLet be a natural number with , let be the initial segment determined by , and let be the set of real numbers with the operations and the order of its ordered field structure, with the absolute value written . On Euclidean space…Increment Bound for a Convex Function through an Extended Point
lemmalem:convex-function-increment-bound-2026aAnalysisMultivariable CalculusLet be a natural number with , let be the set of real numbers with the operations and the order of its ordered field structure, let be a convex subset of Euclidean space , a real vector space by…A Convex Function Bounded Above on a Set Symmetric about a Point is Bounded Below on It
lemmalem:convex-function-bounded-below-reflection-2026aAnalysisMultivariable CalculusLet be a natural number with , let be the set of real numbers with the operations and the order of its ordered field structure, let be a convex subset of Euclidean space , a real vector space by…A Convex Function is Bounded Above near a Point by its Values at Coordinate Neighbours
lemmalem:convex-function-bounded-above-crosspolytope-2026aAnalysisMultivariable CalculusLet be a natural number with , let be the initial segment determined by , and let be the set of real numbers with the operations and the order of its ordered field structure, with the absolute value written . Let be a convex su…Determinant Bound for a Matrix Squeezed between a Negative Multiple of the Identity and Zero
corollarycor:determinant-bound-semidefinite-interval-2026aAnalysisLinear AlgebraLet be a natural number, let be the initial segment determined by , and let be the set of real numbers with the operations and the order of its ordered field structure, with the absolute value written . Let with…Hadamard's Inequality for a Positive Semidefinite Matrix
theoremthm:hadamard-determinant-inequality-psd-2026aAnalysisLinear AlgebraLet be a natural number, let be the initial segment determined by , let be the set of real numbers with the operations and the order of its ordered field structure, and let be a symmetric positive semidefinite real matrix, with entr…The Determinant of a Triangular Matrix is the Product of its Diagonal Entries
lemmalem:determinant-triangular-2026aAlgebraLinear AlgebraLet be a natural number, let be the initial segment determined by , ordered by the relations of Order on the Natural Numbers, and let be a real matrix. Call lower triangular if whenever and , and upper triangular if…- Let be a natural number, let be the initial segment determined by , and let and be real matrices. Let be the matrix product, and let determinants be read as in Row Properties of the Determinant. Then
- Let be a natural number, let be the initial segment determined by , and let be the set of real numbers with the operations and the order of its ordered field structure. Let be a real matrix, with entry notation as there. Let …
- Let be a natural number, let be the initial segment determined by , and let be the set of permutations of , with the identity , the composition and the inverse of…
An Injective Self-Map of a Finite Set is a Bijection
lemmalem:injective-self-map-finite-set-bijective-2026aCombinatoricsSet TheoryLet be the set of natural numbers with successor map as in that definition, let , and let be the initial segment determined by . Call a map between sets injective if implies for all . The notions…Permutations of an Initial Segment Form a Group under Composition
lemmalem:permutation-group-2026aAlgebraCombinatoricsLet be a natural number, let be the initial segment determined by , that is, the set , and let be the set of permutations of , that is, the set of bijections from to . For maps let be th…Generalized Distributivity: Expanding a Product of Finite Sums
lemmalem:generalized-distributivity-2026aAlgebraSet TheoryLet be a field. Let be the set of natural numbers with successor map as in that definition, let , and let and be the initial segments they determine. Let be an -tuple of -tuples in , with components written …The Product of Two Sums over Finite Index Sets is a Sum over the Cartesian Product
lemmalem:finite-set-indexed-sum-product-2026aAlgebraSet TheoryLet be a field, let and be nonempty finite sets, and let and be maps. Let be the Cartesian product of and , formed with the ordered pair; it is nonempty, and it is finite by claim 1 of…Peeling, Splitting, and Interchange for Sums over a Finite Index Set
lemmalem:finite-set-indexed-sum-peeling-2026aAlgebraSet TheoryLet be a field, with additive identity . Let be the set of natural numbers with successor map as in that definition. The notions finite and has elements are those of the indicated definitions. Sums over a finite index set are those of…- Let and be sets, and write and for the identity maps, given by and . For maps and let be the map with , and let…