Editing Operator theory (section)

{{Short description|Mathematical field of study}}
In [[mathematics]], '''operator theory''' is the study of [[linear operator]]s on [[function space]]s, beginning with [[differential operator]]s and [[integral operator]]s. The operators may be presented abstractly by their characteristics, such as [[bounded linear operator]]s or [[closed operator]]s, and consideration may be given to [[nonlinear operator]]s. The study, which depends heavily on the [[topology]] of function spaces, is a branch of [[functional analysis]].

If a collection of operators forms an [[algebra over a field]], then it is an [[operator algebra]]. The description of operator algebras is part of operator theory.