Extensors

In this paper we introduce a class of mathematical objects called extensors and develop some aspects of their theory with considerable detail. We give special names to several particular but important cases of extensors. The extension, adjoint and generalization operators are introduced and their properties studied. For the so-called $(1,1)$-extensors we define the concept of determinant, and their properties are investigated. Some preliminary applications of the theory of extensors are presented in order to show the power of the new concept in action. An useful formula for the inversion of $(1,1)$-extensors is obtained.