Abstract
In this first lecture, we'll look at the physical processes that govern the interaction between two atoms: how do they behave when they approach each other? Do they attract, repel or form a bonded state (dimer)? These questions belong as much to chemistry as to physics, but we'll see that the most important elements for us are not necessarily those emphasized in "traditional" chemistry and molecular physics lectures. In particular, the fact that we are approaching the problem from the point of view of cold atoms and quantum gases will give a crucial role to the long-range behavior of the interaction potential.
