Andrés Franco Grisales: Robertson-Walker spacetimes and the big bang

[Note: this talk was originally planned for October 28th, but has been moved to November 4th.]

We discuss how cosmological models in general relativity support the big bang as a theory for the beginning of the universe. After a brief introduction to the basic concepts of semi-Riemannian geometry, we define the models of interest, the Robertson-Walker spacetimes. Then show how these models, along with some astronomical data, suggest that the universe started with a big bang singularity.