Planar binary trees in scattering amplitudes

Abstract

These notes are a written version of my talk given at the CARMA workshop in June 2017, with some additional material. I presented a few concepts that have recently been used in the computation of tree-level scattering amplitudes (mostly using pure spinor methods but not restricted to it) in a context that could be of interest to the combinatorics community. In particular, I focused on the appearance of planar binary trees in scattering amplitudes and presented some curious identities obeyed by related objects, some of which are known to be true only via explicit examples.