Reducing Traffic Wait Times

I was watching traffic today, and I noticed yet again a phenomenon that I've thought about many times before. It happens when a long line of cars is stopped, bumper to bumper, and then the car that's first in line begins to move. It always takes a moment for the car behind the first car to start moving. And then it takes another moment for the third car to start moving, and so on, back down the line of cars. These "moments before moving" get magnified the more cars there are, so that cars further back in line have to wait for every car in front of them to go through their moment before moving.

The observation is that tiny spaces of time where one car has to wait for another get compounded such that they have disproportionately huge effects on the cars in the back of a line. Theoretically, in the situation outlined above, if every car in a line began to move at the exact same moment and with the exact same acceleration as the first car in the line, no one would have to wait at all. Everyone would advance at the same time, much the same way train cars all move together. Of course, this idealized situation is probably impossible, especially with human drivers behind the wheel.

Enter Google's self-driving cars. NPR informed me (yeah, NPR again, look, as much as I love FM 93.3, 99.5, 103.5, and 106.7, there's only so much I learn from those stations...) that the self-driving cars can predict traffic patterns by bouncing signals off the pavement and underneath the cars in front of it. Suppose everyone had a self driving car - I imagine we'd be able to get pretty close to a line of cars all starting to move at the same time. Do it, Google!