Geometry of kinematic flow

In this talk I will discuss a geometric organisation of the differential equations for the correlation functions of conformally coupled scalars in power-law cosmologies. To do this, I will introduce a basis of functions inspired by a decomposition of the correlators into time-ordered components and explore how this is related to the arrangement of hyperplanes in energy space. Expressing these functions as graph tubings allows us to deduce the differential equations from just two straightforward rules—activation and merger. The merger rule can alternatively be understood as the collapse of time ordered propagators, helping to demystifying the origin of the kinematic flow.