The Algebra of the Riemann Curvature Tensor in General Relativity: The Relation of the Invariants of the Einstein Curvature Tensor to the Invariants Describing Matter

In this paper, the second in a series of papers on the algebra of the Riemann curvature tensor, we relate the algebraic invariants of the Einstein curvature tensor to the algebraic invariants of the trace‐free part of the Ricci tensor, and, consequently, to the trace‐free part of the stress‐energy tensor for the physical system. We also show explicitly how all of the components of the trace‐free part of the Ricci tensor transform under a Lorentz transformation.