New York taxis and quantum mechanics

There’s a generally held belief in theoretical and applied physics that nothing is continuous and everything comes in discrete packets (quanta). Light, atomic particles, even time, have their own quantum behaviour and their own sizes for a quanta. Furthermore, these entities possess both wave and particle natures. My old physics teacher used to call these wavicles. Now this discrete nature of things is only really "observable" at the microscopic level; where we live, on the macroscopic level, our eyes, senses and most machines simply can’t discern the individual quanta and we perceive them as continuous.

So where’s all this leading, you might ask? Well I’m in New York at the moment at the Web Services on Wall Street conference. I just flew into Kennedy and while waiting for a taxi at the airport I realised that every single time I’ve been here before it always goes the same way: you get off the plane, spend 50 minutes going through customs and then spend another 50 minutes waiting for a taxi; when they do arrive, they always turn up in fours. So, the size of an airport taxi-quanta is 4. My question is: why? Is there some physical process that does that, or is it some fundamental law of the universe? Whatever the reason, after travelling for over 12 hours, as Eric Cartman would put it, that extra wait p*sses me off! And let's not forget that there's always some taxi-rank "conductor" (sorry, can't think of the right term at the moment) who seems to think that blowing a whistle really loud will make things better. No, all it does it deafen the people standing in the queue!!

BTW, taxi’s also exhibit other quantum behaviour, specifically Heisenberg’s Uncertainty Principle, which in one of its incarnations says that you can’t measure position and momentum precisely. For taxis, if you need a taxi you can never find one though there are always plenty of empty ones speeding around; when you don’t want one, there are plenty parked in the road!