For those interested in delving deeper into the science of cosmology, Andrew Liddle’s An Introduction to Modern Cosmology helps to bridge the gap between popular science and graduate level reference books. He arrives at the famous Friedmann equation through Newtonian physics rather than the standard relativistic approach (we still end up with the same equation). Through the solutions of this equation, Liddle explores subjects such as the curvature of space, the cosmological constant, the density parameter, the age of the Universe, nucleosynthesis, and inflationary big bang models. Due to the author’s use of mathematical equations to explain these concepts, readers are expected to be familiar with very basic undergraduate level mathematics and physics.