Developments in GRworkbench

AbstractThe software tool GRworkbench is an ongoing project in visual,numerical General Relativity at The Australian National University.Recently, GRworkbench has been significantly extended to facilitatenumerical experimentation in analytically-defined space-times. Thenumerical differential geometric engine has been rewritten using func-tional programming techniques, enabling objects which are normallydefined as functions in the formalism of differential geometry and Gen-eral Relativity to be directly represented as function variables in theC++ code of GRworkbench. The new functional differential geometricengine allows for more accurate and efficient visualisation of objects inspace-times and makes new, efficient computational techniques avail-able. Motivated by the desire to investigate a recent scientific claimusing GRworkbench, new tools for numerical experimentation havebeen implemented, allowing for the simulation of complex physicalsituations. 1 Introduction Physically important exact solutions of the Einstein field equationare often difficult to work with algebraically because of their com-