  The scaled relative graph (SRG) of an operator is a subset of the complex
plane. It captures several salient features of an operator, such as
contractiveness, and can be used to reveal the geometric nature of many of the
inequality based arguments used in the convergence analyses of fixed point
iterations. In this paper we show that the SRG of a linear operator can be
determined from the numerical range of a closely related linear operator.
Furthermore we demonstrate that the SRG of a linear operator has a range of
spectral and convexity properties, and satisfies an analogue of Hildebrant's
theorem.
