This is a list of functional analysis topics.
See also: Glossary of functional analysis.
Hilbert space
- Bra–ket notation
- Definite bilinear form
- Direct integral
- Euclidean space
- Fundamental theorem of Hilbert spaces
- Gram–Schmidt process
- Hellinger–Toeplitz theorem
- Hilbert space
- Inner product space
- Legendre polynomials
- Matrices
- Mercer's theorem
- Min-max theorem
- Normal vector
- Orthonormal basis
- Orthogonal complement
- Orthogonalization
- Parallelogram law
- Semi-Hilbert space
- Parseval's identity
- Rayleigh quotient
- Reproducing kernel Hilbert space
- Riesz representation theorem
- Rigged Hilbert space
- Spectral theorem, Spectral theory
- Trace class
Functional analysis, classic results
- Normed vector space
- Unit ball
- Banach space
- Hahn–Banach theorem
- Dual space
- Predual
- Weak topology
- Reflexive space
- Polynomially reflexive space
- Baire category theorem
- Open mapping theorem (functional analysis)
- Closed graph theorem
- Uniform boundedness principle
- Arzelà–Ascoli theorem
- Banach–Alaoglu theorem
- Measure of non-compactness
- Banach–Mazur theorem
- Bounded linear operator
- Spectral theory
- Topologies on the set of operators on a Hilbert space
- Singular value (or S-number)
- Fredholm operator
- Fuglede's theorem
- Compression (functional analysis)
- Friedrichs extension
- Stone's theorem on one-parameter unitary groups
- Stone–von Neumann theorem
- Functional calculus
- Hilbert–Pólya conjecture
Banach space examples
Real and complex algebras
- Uniform norm
- Matrix norm
- Spectral radius
- Normed division algebra
- Stone–Weierstrass theorem
- Banach algebra
- *-algebra
- B*-algebra
- C*-algebra
- Positive element
- Positive linear functional
- operator algebra
- Gelfand representation
- Gelfand–Naimark theorem
- Gelfand–Naimark–Segal construction
- Von Neumann algebra
- von Neumann double commutant theorem
- Topological ring
- Noncommutative geometry
- Disk algebra
- Colombeau algebra
Amenability
Quantum theory
See also list of mathematical topics in quantum theory