Exploring Rule 184, a one-dimensional cellular automaton that models…

Exploring Rule 184, a one-dimensional cellular automaton that models cars on a single-lane road at the bottom of the frame.

+ White squares are open road
+ The black squares are moving cars
+ The red squares show cars that can’t move forward

Cars move forward if the space ahead is clear. If not, they stop—forming traffic jams.

The jams ripple backward through time, like waves running upstream. It’s just like the brake lights on Hwy 101 outside my window right now.