Today I watched a pigeon commit suicide. I mean, he really stayed up there contemplating for like, ten or fifteen minutes. I was waiting in line for a sandwich so I didn't have much else to do but stand and watch. The thing about eliminating your own map via tall city building if you're a pigeon is that the rescue team doesn't have to shout with one of those bull horns from the ground level to try to talk some sense into you. They can literally fly right next to you and have a chat about whatever they chat about. Usually things like, "you don't have to do this," "what would your mother say?" or, "think about your little sister," etc, I think. You could even have some friends fly up there and bring you a few beers, watch the baseball game together through some guy's window, who is probably also drinking a few beers. All of this makes this choice of the pigeon's, I mean standing on the ledge and going for the ultimate plummet, seem pretty awkward. He could have just flown in front of a train, stayed in the middle of the street when a car tried to pass, or even kept his place on the sidewalk while hundreds of tourists herded through town without even looking where they were going. The spectacle, though. It's all about the show, the statement, the message to your fellow community. I still don't know why he chose the old fashion face first dive.
The thing was strange to watch, notwithstanding the awkward fact that this pigeon had made up his mind that it was over. I mean, you see a pigeon fall, and it's like, he could just save himself at any moment by flying away. So I was standing there like expecting a spectacular recovery, one all his friends would be proud of. But, nothing. Just: thump. The bird must have really been fed up, to go out like that and all.
But the way that it looked, that was the most intriguing part, falling with like a blatant disregard for the law of conservation of angular momentum. The bird stood up there, perched right, kind of walking back and forth, bobbing his head in and out, looking at something on the roof, looking up, looking back down, sort of sizing up his options I guess. So then the moment came. He's all in. No escape.
Actually here's another fascinating thing. For a bird, the ledge does not equal the point of no return, does it? He's got like a few more seconds where he's got to be committed to the fall, so he doesn't abort the mission and all. But he's decided to take the first step now, at the ledge. He's facing forward, away from the building, looking out over the other buildings and toward the rest of the city, head held high, proud. His feet are wrapped around the railing as he pivots forward. It starts slowly. At first it's not clear, maybe he's just a little inebriated and losing his balance. But then he speeds up, pivoting downward, head now racing toward the horizontal position. This circumstance, the force of gravity on the center of mass of the bird combined with the fact that his feet are attached to the railing, sets up what is called in the profession of physics, and, like, many other mechanical trades, a lever arm. This generates an initial amount of angular momentum so that as the bird decides to let go, he may not have a lot of self confidence, but what he's got is a lot of angular momentum.
At this point, it's hard to say what's going through the poor little guy's cranial nervous system. He's probably actually pretty nervous. As he pivots down, when he reaches approximately a horizontal position, his wings puff up and you could almost think he was about to abort. But it's just a brief little puff as the air rushes up between his wings and his body. He must be pretty relaxed, actually, because this puff seems to catch him off guard. But then he quickly pulls his wings in, bodyward.
And then all the angular momentum just seems to, like, vanish. He is pivoting downward, gravity generating the A.M. and then he decides to let go. Then the puff thing happens. Now the sucker's really falling, not attached to anything. Hundreds of years of physical intuition would tell you that this bird should keep rotating, head over heels if you will, while he falls, so the good old angular momentum vector L doesn't change because now that he's let go the lever arm is gone. Rotational and translational motion decoupling is what we should have here.
But what really happened was when his head finally reached the maximum downward position, all rotational motion stopped and this poor guy was swan diving like a bullet directly for the pavement, which I guess he didn't really see, given the position of his eyes and all. He was more like looking up and down the street to see if anything interesting was going on. Come on, he must have known he was the only show on this block on this AM.