It a long title for a small paper that provides a decent overview. I’ll be honest, I’m struggling to get a grip on the PDE side of GR. Oh I don’t have much of a problem with the notation, the concepts, or the methods. What I do have a problem with is the motivation. I just don’t understand why certain assumptions are made, why certain cases are considered important or of the relevance of certain results. I feels a little like my own personal black hole.

Frauendiener’s paper has been very helpful to me as it cuts through most of the (often needed) technical detail. It presents the motivation and the results but without the sometimes over powering generalisation (as I sometimes find it).

In essence the paper presents what are called the Conformal Field Equations. These equations are equivalent to the Einstein Field Equations but are reformulated explicitly as a symmetric hyperbolic system in a particular set of equations.

The equations are presented without derivation along with a section on space spinors. This plus the sections discussing motivation mean that the paper is more like a buffet.

Fortunately this is what I currently need…