List of lemmas

This following is a list of lemmas (or, "lemmata", i.e. minor theorems, or sometimes intermediate technical results factored out of proofs). See also list of axioms, list of theorems and list of conjectures.

Algebra

Algebraic geometry

Category theory

A commutative diagram that illustrates the five lemma

Linear algebra

Group theory

Polynomials

Ring theory and commutative algebra

Universal algebra

Analysis

Complex analysis

Fourier analysis

Differential equations

Differential forms

Functional analysis

Mathematical series

Numerical analysis

Applied mathematics

diagram of a length-8 fast Fourier transform
diagram of a length-8 fast Fourier transform

Control theory

Computational complexity theory

Cryptography

Formal languages

Microeconomics

Combinatorics

Graph theory

Order theory

Dynamical systems

Geometry

Euclidean geometry

Hyperbolic geometry

Metric spaces

Riemannian geometry

Mathematical logic

Set theory

Number theory

Analytic number theory

Diophantine equations

Sieve theory

Probability theory

Statistics

Measure theory

Topology

Differential topology

Fixed-point theory

An example of a covering described by the Knaster–Kuratowski–Mazurkiewicz lemma

Geometric topology

Topological groups and semigroups