Spacetime Engineering

Spacetime engineering refers to the construction of gravitational fields that satisfy the Einstein equations with or without matter. The intention is to produce solutions that are sufficiently realistic to be of interest in either cosmological or astrophysical settings. The nonlinearity, coupling, and coordinate freedom of the gravitational equations force two things: (1) sorting out the pieces of the gravity and matter variables that are relatively simple and can be put back together in a natural way, and (2) using numerical methods for reassembly and propagation of the pieces. In this article the author outlines a handbook for process (1) and some recent results that he hopes soon will become part of the lore of the subject.