Advances in technology have brought us huge data which inform us about the state of our Universe at the present time. A major problem in astrophysics is to reconstruct the past history of the Universe and

retrieve its initial conditions from these data. I shall show that this inverse problem finds a natural and unique solution through optimal transport theory. I shall report on results of the application of our efficient semi-discrete algorithm to hundreds of millions of data points. I will also briefly discuss results from the first numerical simulations of the Monge-Ampère gravity based on optimal

transport theory.

Bio: Roya Mohayaee obtained her doctorate from Imperial College, London. She then had postdoctoral positions in Cambridge/UK, Padova/Italy and since 2006, she is a faculty at department of physics (institute of astrophysique) of Sorbonne Université in Paris. She works in the field of cosmology and in particular on the mathematical modelling of the evolution of the Universe.