Free online courseCosmology Fundamentals: Hubble’s Law, FLRW Models, Inflationand Structure Formation

Course Description

Cosmology Fundamentals: Hubble’s Law, FLRW Models, Inflation and Structure Formation is a free online astronomy course from Zewail City that builds a clear pathway from the basic language of cosmology to the modern picture of an expanding universe. It begins by sharpening essential tools such as units and dimensions, then moves into the observational foundations that reveal cosmic expansion through Hubble’s law.

You will connect intuitive Newtonian ideas with relativistic cosmology, developing the concepts needed to describe a homogeneous and isotropic universe. Along the way, you will work with the FLRW metric, compare matter- and radiation-dominated eras, and explore illustrative cases such as the Milne universe. Key spacetime concepts are developed through horizons and conformal diagrams, helping you interpret what can and cannot be observed across cosmic history.

The course then focuses on how we measure the universe: redshift, distance measures, angular size, luminosity relations, and number counts, tying theory to observational cosmology. You will also examine the universe’s composition and thermal history, building context for major transitions in the early cosmos.

Finally, the course dives into inflation and its role in explaining large-scale structure, followed by an introduction to modified gravity through f(R) models. The closing sections develop structure formation via gravitational instability, starting with Newtonian treatments and extending to general relativity, giving you a coherent framework for understanding how small perturbations evolve into the cosmic web seen today.