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Showing 31–60 of 360 reference entries

Mathematics & logic · PhysicsFundamental theorem of calculus

Continuity connects differentiation with integration.

Mathematical statement
Mathematics & logic · InformationProbability space and axioms

A probability assigns nonnegative, normalised, countably additive weights to events.

Definition
Mathematics & logic · InformationConditional probability and independence

Conditioning restricts attention to an event of positive probability.

Definition
Mathematics & logic · InformationExpected value of a discrete random variable

Expected value weights possible values by their probabilities.

Definition
Mathematics & logic · MeasurementConfidence interval for a population mean

A confidence level describes repeated-sampling coverage of an interval procedure.

Method
Information · Mathematics & logicBits and unsigned binary encoding

A bit has two possible states; a fixed-width unsigned binary word encodes an integer.

Definition
Information · Mathematics & logicShannon entropy of a discrete distribution

Shannon entropy measures uncertainty in a specified probability distribution.

Definition
Information · Mathematics & logicUndecidability of the halting problem

No total algorithm decides halting for every program and input in a general computation model.

Mathematical statement
Information · Mathematics & logicAsymptotic upper bounds and big O

Big O bounds eventual growth up to a fixed constant factor.

Definition
Measurement · Mathematics & logicFirst-order uncertainty propagation

Combine input uncertainty through a measurement model.

Method
Measurement · Physics · Mathematics & logicDimensional consistency

Use dimensions to detect impossible quantity equations.

Method
Physics · Mathematics & logicInvariant spacetime interval

Lorentz transformations preserve a combined space-time separation.

Model
Mathematics & logicFirst-order predicates and quantifiers

Quantifiers bind variables over a specified domain.

Definition
Mathematics & logicZFC set-theory framework

Set existence is governed by explicit axioms and schemas.

Definition
Mathematics & logicCompleteness of the real numbers

Upper-bounded nonempty real sets have least upper bounds.

Mathematical statement
Mathematics & logicFinite and countable sets

Countability includes finite sets in this convention.

Definition
Mathematics & logicEquivalence relations and quotient classes

An equivalence relation partitions a set into classes.

Definition
Mathematics & logicModels, completeness and incompleteness

Semantic consequence and arithmetic completeness are distinct.

Mathematical statement
Mathematics & logicInteger divisibility and the Euclidean algorithm

Repeated division computes a greatest common divisor.

Method
Mathematics & logicUnique prime factorization of integers

Positive integers greater than one have unique prime factors.

Mathematical statement
Mathematics & logicInteger arithmetic modulo n

Congruence identifies integers differing by a multiple of n.

Definition
Mathematics & logicChinese Remainder Theorem

Coprime moduli specify one combined residue.

Mathematical statement
Mathematics & logicGroups and abelian groups

A group has associative composition, identity and inverses.

Definition
Mathematics & logicGroup homomorphisms and kernels

Homomorphisms preserve the group operation.

Definition
Mathematics & logicRings and identity conventions

A ring combines addition with distributive multiplication.

Definition
Mathematics & logicFields and division

A field allows division by every nonzero element.

Definition
Mathematics & logicFundamental Theorem of Algebra

Nonconstant complex polynomials factor into linear terms.

Mathematical statement
Mathematics & logicMetric spaces

A metric supplies a distance satisfying three axioms.

Definition
Mathematics & logicTopological spaces

A topology specifies which subsets are open.

Definition
Mathematics & logicCompactness and finite subcovers

Compactness reduces every open cover to a finite one.

Definition