I'm not an Uber driver, but several times when I've been waiting by the curb to pick up my wife at her office, Uber passengers have jumped in my back seat. Where do I submit my reviews of them?

Nathan has a conference paper with a lot more detail about the physics. PDF here: http://webusers.npl.illinois.edu/~a-nathan/pob/ProcediaEngineering34KBall.pdf