One of the more annoying points of contention back in the days of the Sokal hoax and the “Science Wars” was an argument over social construction. This is, loosely speaking, the idea that our understanding of the world is not strictly rational and objective, but is heavily influenced by interactions with other people, and the culture in which we live. The idea originally arose in literary academia, but expanded to be applied to basically everything, including science.
At bottom, this is probably the best and most useful idea to come out of whatever collective “-ism” you want to use to refer to 20th century scholarship in the arts and literature. Applied in a reasonable manner, it ought to be fairly uncontroversial– it’s not hard to come up with examples of theories that were accepted more quickly or rejected out of hand because of who proposed them, and anybody who’s done research knows that there are a lot of factors beyond pure science that go into how scientists choose what to study, and how results are interpreted.
The problem is that once you have a hammer, everything starts to look nail-shaped, and good ideas get ridiculously overextended. This is true in physics, as well– the tendency of aging physicists to wander off and start reinterpreting whole other fields of inquiry in terms of a handful of physics concepts is well documented and regrettable. In the case of the science wars stuff, this led to various post-whateverist scholars claiming that there was no objective reality, and science was entirely a collection of social constructs. A position that was rightly regarded as ludicrous, and led to the Sokal business, where a prominent journal published a bunch of gibberish that NYU physicist Alan Sokal slapped together, and was embarrassed by the revelation of the hoax.
Of course, there were a fair share of annoying arguments from the science side, as well, where a number of scientists took positions opposing the entire idea of social construction, which is in its way just as blatant a rejection of obvious truth as anything from the post-whateverists. One of the rhetorical devices frequently employed by this group was to ask mocking questions like “So, is gravity a social construct?” Which, like most such arguments, is correct in a narrow, technical sense while also being not nearly as convincing as the geeks who deploy it think.
Which made it interesting, these past couple of weeks, to see a dramatic demonstration of the social construction of gravity in a quasi-real context. I’m referring here to the short, spectacular life of the touch-screen game “Flappy Bird,” which was removed from both iTunes and Google Play over the weekend, to general bafflement as to why anybody would shut down such a successful game.
The game is, as I was telling a colleague in CS on Friday, simple and stupid enough that you could probably assign “Write ‘Flappy Bird’” as a homework problem in a low-level programming class. It’s a pixellated little blob of a bird that flaps its wings when you tap the screen and falls when you don’t, and the goal is to fly it through a series of Super Mario pipes without touching anything. It’s ridiculously difficult, though, and weirdly addictive.
The difficulty stems largely from the fact that the bird falls really fast, which prompted a lot of folks to take to social media and grumble about how the physics of the game couldn’t possibly be right. This was like a bat-signal sent up to physics bloggers, and Frank Noschese took up the challenge, using video analysis to show that the little blob of pixels does, in fact, fall with a constant acceleration, and that if you assume the bird is the size of a real bird, it falls at a rate consistent with real-world gravity. He put together a really nice demo of this, with a pair of iPads showing video of Flappy Bird next to video of a colleague dropping a basketball:
The two objects stay at the same height all through the fall, showing that they’re falling at the same rate.
(This is not to say that the physics is perfect– as Frank also noted, the “flap” is a little dodgy, as the bird always ends with the same upward velocity, regardless of how fast it was falling before the “flap.” That’s the other big factor contributing to the difficulty of the game.)
So, why all the outrage? Well, because of the social construction of videogame gravity. As Flappy Bird shows, when you put realistic gravity into video games, they’re really hard. So, while games like Angry Birds and Fruit Ninja use a constant vertical acceleration, they crank down the acceleration of gravity to make the game easier. If you put in a realistic acceleration, they would be ridiculously difficult.
People got outraged about the physics of Flappy Bird because years of previous games had conditioned them to expect a lower acceleration, leading to easier gameplay. We’ve socially constructed an expected acceleration of gravity in videogame worlds, and when that expectation was confounded by reality, people got peeved.
Now, does this mean that the real physics of gravity is also purely a social construct? Not purely, no. There’s unquestionably a bit of social dynamics involved in the development and acceptance of general relativity, our best current theory of gravity, but the underlying phenomenon is unquestionable. A different set of social circumstances and dynamics might’ve led to us using different language to talk about it, but in the universe where that happened, objects would still fall when dropped near the surface of the Earth, and Flappy Bird would still be maddeningly difficult to play.
(This is a longer version of stuff I said in last week’s Uncertain Dots hangout with Rhett, but I offer it as a tribute to the passing of the game. Godspeed, Flappy Bird, you annoyingly fragile little bastard.)