Moshers’ behavior at heavy metal concerts similar to disordered 2D gas

The behavior of crowds at heavy metal concerts is mathematically similar to a disordered 2D gas, physicists have found.

In these crowds, fans often form circles called mosh pits and then run together with physical abandon, bouncing off one another with arms flaying and legs kicking, technologyreview.com says, citing the study.


“The collective mood is influenced by the combination of loud, fast music (130 dB, 350 beats per minute), synchronized with bright, flashing lights, and frequent intoxication,” Jesse Silverberg and pals at Cornell University in Ithaca have said.


The resulting disorder may sound chaotic but Silverberg and co say it turns out to have all the properties of self-organised emergent behaviour. Today, they are said reveal the results of their study of this phenomenon.


Silverberg and co gathered their data by examining videos of mosh pits on You Tube,These crowds contain anything from 100 to 100,000 people. After correcting for camera shake and distortions in perspective, they used particle image velicometry techniques to measure the collective motion of moshers.


What they discovered was that the speed distribution of moshers closely matches that of molecules in a 2D gas at equilibrium.
To answer is that they simulated the behaviour using a standard flocking simulation software in which they could vary parameters such as self-propulsion and flocking behaviour. They found they could easily reproduce the actually behaviour of moshers when the self-propulsion and flocking parameters were dominated by noise.