Explore the intricacies of the Riemann tensor in this graduate-level lecture from the Warsaw4PhD and GeoPlanet PhD schools' Autumn/Winter 2023-2024 semester. Delivered by Mikołaj Korzyński from the Center for Theoretical Physics, Polish Academy of Sciences, the lecture covers three main topics: Christoffel symbols and geodesics in the Newtonian approximation, the Riemann tensor of a 2-sphere, and the Riemann tensor in Rindler's accelerating spacetime. Gain a deeper understanding of these advanced concepts in theoretical physics over the course of just over an hour.