On 1 April 2020 I gave a talk in the Monash topology seminar.

**Title: **Circle packings, Lagrangian Grassmannians, and scattering diagrams

**Abstract: **I’ll discuss some recent work, in progress, relating the theory or circle packing to various ideas in geometry and physics. In paticular, we’ll show how ideas of Penrose and Rindler can shed light on circle packings, describing them by spinors or by Lagrangian planes satisfying various conditions. We’ll also touch on how the resulting spinor equations are related to on-shell diagrams in scattering theory.

Monash topology talk on Circle packings, Lagrangian Grassmannians, and Scattering Diagrams, April 2020