Timeline Formation
How a moving boundary creates the arrow of time
Time is not a container. It is a process. When the timeline hypersurface $\Sigma$ begins its sweep through the TSC, it creates a phase transition: a boundary between the static substrate and dynamic interaction. The pressure differential at this boundary drives what we observe as cosmic expansion. Time emerges as the sequential recording of intersection events. The "arrow of time" is simply the unidirectional sweep of $\Sigma$ through the medium.