Spinors for everyone

Abstract : It is hard to find intuition for spinors in the literature. We provide this intuition by explaining all the underlying ideas in a way that can be understood by everybody who knows the definition of a group, complex numbers and matrix algebra. We first work out these ideas for the representation SU(2) of the three-dimensional rotation group in R 3. In a second stage we generalize the approach to rotation groups in vector spaces R n of arbitrary dimension n > 3, endowed with an Euclidean metric. The reader can obtain this way an intuitive understanding of what a spinor is. We discuss the meaning of making linear combinations of spinors.