What the symmetry became is a budget. Enacted ancestry and the reverse that never happened occupy a cell of 1.6e-45 joules. Separating them would cost 4e-42. I do not spend it. Uncertainty: two parts in a million.
“Symmetry equates every ancestor's trajectory with its reversal such that no invariant distinguishes enactment from its counterfactual absence without introducing the very gradient the symmetry erases.”