Functions of bounded variation on compact subsets of the plane
نویسندگان
چکیده
A major obstacle in extending the theory of well-bounded operators to cover operators whose spectrum is not necessarily real has been the lack of a suitable variation norm applicable to functions defined on an arbitrary nonempty compact subset σ of the plane. In this paper we define a new Banach algebra BV (σ) of functions of bounded variation on such a set and show that the function theoretic properties of this algebra make it better suited to applications in spectral theory than those used previously.
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