Kinematic Flow and the Emergence of Time

I will start with a broad overview of the theory of initial conditions of the universe, what we know and what we hope to know in the near future.

Then I will describe some recent work. Motivated by precision calculations in primordial cosmology, a bootstrap approach has been developed over the past few years. A central element in this approach is to determine static differential equations in terms of boundary momenta (at the reheating surface), instead of performing time-evolution integrals. While investigating a toy model of cosmology to better understand these differential equations, we found an autonomous structure, from which time evolution seems to be an output. I will describe the rules of this “kinematic flow,” and mention some work in progress to further develop it.