Materials to accompany lectures for the SIGRAV International School, Feb 2020.

The mathematica notebook here calculates the components of the linearised Einstein field equations for a perturbed FRW metric in conformal Newtonian gauge. It does not require the use of packages like XTensor, Xact, etc.

This notebook was adapted by Tessa Baker (QMUL) from an example by Leonard Parker, University of Wisconsin, Milwaukee for the book 'Gravity: An Introduction to Einstein's General Relativity', by James Hartle.