In mathematics, the term adjoint applies in several situations. Several of these share a similar formalism: if A is adjoint to B, then there is typically some formula of the type
- (Ax,y) = (x, By).
Specifically, adjoint or adjunction may mean:
- Adjoint endomorphism of a Lie algebra
- Adjunction (field theory)
- Adjoint functors in category theory
- Hermitian adjoint (adjoint of a linear operator) in functional analysis
- Adjoint representation of a Lie group
- Adjunction space in topology
- Conjugate transpose of a matrix in linear algebra
- Adjugate matrix, related to its inverse
- Adjoint equation
- The upper and lower adjoints of a Galois connection in order theory
- For the adjoint of a differential operator with general polynomial coefficients see differential operator