

The physics of mosh pits - mzehrer
http://kottke.org/14/11/the-physics-of-mosh-pits

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AdmiralAsshat
Those black dots, which are trying desperately to get OUT of the mosh pit so
that they can watch the damn concert but keep being shoved back in? That's me.
At every.single.show.

~~~
ajvargo
I've seen this many a time. The trick is to come to a stop at the edge, and
then walk out. If you are moving any kind of speed, folks on the edge will
just assume you are disoriented and give you that "helpful" shove back into
the mix.

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washedup
What's interesting is when there are a lower number of people, say 100. With
so much space, the "moshers" tend to just go in one direction until they bump
into another person, but this isn't really accurate. There needs to be some
level of randomness in their movement, so that when there are large spaces
they are not just coasting, but still bouncing around.

That being said, this is pretty fun, and the dynamics for crowded areas looks
appropriate.

~~~
icegreentea
You can get something like what you want by changing the noise strength.

~~~
washedup
Yea, that's definitely an improvement. I would prefer if there was some sort
of "cohesion" measure among the moshing particles. Groups, no matter how
small, tend to stick together.

~~~
icegreentea
That's the flock strength slider. If you turn it down to zero, you get no
flocking, and red particles will only interact via direct physical contact.

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clemsen
Be sure to klick through to the full simulator [0]. Here you can adjust
values, steer the crowd (using a,w,s,d) and see the results at the same time.

[0]
[http://mattbierbaum.github.io/moshpits.js/](http://mattbierbaum.github.io/moshpits.js/)

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aaron695
Interesting but disturbing article on crowd quakes -

[http://arxiv.org/pdf/1206.5856v1.pdf](http://arxiv.org/pdf/1206.5856v1.pdf)

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seanmcdirmid
Once at a Grunttruck concert, for a brief time I was the only one in a small
gap of the mosh pit, just in time to receive the full brunt of a stage dive. I
was out for 10 minutes.

Mosh pits are perfectly safe without stage diving.

~~~
kbart
Hah, reminds an epic stage dive fail of an acquaintance of mine -
[http://www.youtube.com/watch?v=Z4hB562aEDk](http://www.youtube.com/watch?v=Z4hB562aEDk)
(skip to 0:45). He broke his arm then.

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dreamlane
The simulation seems broken when you increase the box size... If the band is
good, most people (black and red alike) will push towards the band.

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mjgoeke
Looks pretty convincing as a model. Just needs some random blank spot every
now and then where they're avoiding the puke on the floor.

