Journal Club

In this presentation, I introduce the relation between the post-Minkowskian (PM) expansion and scattering amplitude methods in general relativity. In recent years, advances in amplitude techniques have enabled new approaches to gravitational problems using the framework of relativistic quantum field theory. Focusing on the two-body problem without spin, I explain how the dynamics of classical gravity can be derived by combining the PM expansion with scattering amplitudes. A central difficulty in this approach lies in the extraction of classical observables from quantum mechanical calculations. In particular, non-analytic terms and the appropriate choice of limits play a crucial role in isolating classical contributions. I discuss how techniques such as the PM expansion, unitarity cuts, and multi-soft limits are employed in this context, and what kinds of results they lead to.