Mosh pits

That is a moshpit simulation, available with working controls here. Why is it here? Because a group of enterprising physics students at Cornell decided to use people's behavior in mosh pits as a stand-in (or proxy) for human motion. During times of calm, they report, humans, like birds or fish, are able to move cooperatively. But what happens during times of panic? That's where the mosh pit comes in.

After analyzing YouTube videos the physicists found that behavior in mosh pits resembles that of atoms in gasses. That's when they came up with the simulation.

In our case, we used two populations of simulated moshers, which we dub Mobile Active Simulated Humanoids, or MASHers.  Active MASHers move around and have a tendency to follow their neighbors (in the technical literature, this is called "flocking"), while passive MASHers prefer to remain stationary.  Mixing active and passive MASHers together, we found that when  . . . flocking dominated randomness, we found an ordered vortex-like state.  Looking back at videos of metal concerts, we found that actual moshers exhibited this vortex-like phenomenon too.  These so-called "circle pits" spontaneously emerge from the simulation and are an interesting example of collective behavior in humans.

Why is this interesting? Because the information may lead to better understanding of the behavior of humans in crowds, they say, leading to better safety design and possibly emergency response.

There are a lot of interesting videos demonstrating posted on the site. And of course the model is fun to play with.