Fans often form circles and then run together with physical abandon

February 13, 2013 4:16 PM

Moshers, Heavy Metal and Emergent Behaviour: The collective behaviour of moshers at heavy metal concerts is mathematically similar to a disordered 2D gas, say physicists.

Silverberg and co gathered their data by examining videos of mosh pits on You Tube, such as this one and this one. 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.

That’s curious. “Why does an inherently non-equilibrium system exhibit equilibrium characteristics?”, they ask.

posted by not_the_water (36 comments total)

The one and only time I moshed, I was the particle which got knocked down, kicked in the throat (by accident, as far as I could tell) and crawled out of the pit.
posted by The Card Cheat at 4:22 PM on February 13 [3 favorites]

I think that's the first question everyone asked. *rolls eyes*
posted by not_the_water at 4:22 PM on February 13 [5 favorites]

Is this really 'emergent' behavior, since most mosh pits have rules that are either unspoken or straight up directed by the singer (Gallows was really bad with this, forcing a circle pit and a wall of death).
posted by Charlemagne In Sweatpants at 4:29 PM on February 13 [2 favorites]

I recently discovered that cold weather mosh pits are amazing. Not only is the crowd way warmer than anywhere else, but everyone is in coats and well padded... you just sort of bounce off each other.
posted by Strass at 4:30 PM on February 13 [5 favorites]

I believe this follows from one of Newton's Laws: A body will remain in motion unless acted upon by security forces.
posted by twoleftfeet at 4:58 PM on February 13 [7 favorites]

Weird, I was just watching a rerun of Numb3rs last night.
posted by fshgrl at 5:00 PM on February 13

Everybody's doing the toxic waltz
Kick your friend in the head and have a ball
Come on and do the toxic waltz
And slam your partner against the wall
Everybody's doing the toxic waltz
Good friendly violent fun in store for all
Get up off your ass and toxic waltz
If you hit the floor
You can always crawl!
posted by 445supermag at 5:01 PM on February 13 [2 favorites]

Brian Posehn: Metal By Numbers
posted by Renoroc at 5:02 PM on February 13 [1 favorite]

So, let's spin kick our ways to better bodies,
Stage dive our way to awesome abs.
And we'll windmill our way to buffer biceps
And mosh the fat out of our ass

So we say lets lose that extra weight,
And today, we'll mosh the pounds away. Get up and dance.


posted by Charlemagne In Sweatpants at 5:08 PM on February 13

And people on the edges of mosh pits exhibit dampened Brownian motion, punctuated by periods where they get pissed off at all the mosh pit atoms and inject a good amount of shoving energy into the mosh pit system.
posted by mod zero at 5:13 PM on February 13 [9 favorites]

Sort of related ... my very first MeFi post
posted by philip-random at 5:20 PM on February 13

Just remember, no lit cigarettes or glass in the disordered 2D gas. If someone falls down in the 2D gas, help them up. If someone wants to leave the 2D gas, let them. The 2D gas is about enjoying the music. The 2D gas is not about hurting people or working out your macho violence bullshit.
posted by TheWhiteSkull at 5:27 PM on February 13 [26 favorites]

Weird, I was just watching a rerun of Quincy M.E. Iast night.
posted by item at 5:35 PM on February 13 [2 favorites]

So what molecules are these?

1.) The 300 pound skinhead with his little head-kicking buddy on his shoulders
2.) The guy who knocks LittleSkinhead off BigSkinhead, sending them both careening william and nilliam
3.) The brodawgs who just show up start pushing people into each other and then bitch and pout when people tell them to knock it off
4.) The one really sweaty shirtless guy who hugs everyone and is apparently On Something (HE LOVES YOU MAN)
5.) The dude with the green mohawk that is basically one horn that is secretly awesome and taking care of everyone
6.) The yahoo with the dreadlocks and the striped stocking cap who thinks people are going to catch him when he stage dives
7.) The itty bitty teeny weeny nerdy metal chick whose feet never touch the floor the entire show
8.) The drunk who pulls a girl's pants off
9.) The five guys who throw the asshole out because where the fuck is security seriously
10.) The singer who jumps offstage to help throw the asshole out
posted by louche mustachio at 6:02 PM on February 13 [11 favorites]

Brownian moshing
posted by Blazecock Pileon at 6:05 PM on February 13 [3 favorites]

item: "Weird, I was just watching a rerun of Quincy M.E. Iast night."

You're the one who's guilty!
posted by symbioid at 6:36 PM on February 13

Do moshers collide elastically? Or do shows pump people up at the same rate as they lose energy due to collisions?
posted by EtzHadaat at 6:44 PM on February 13

Floor-punching is mathematically similar to the molecular vibrations of gaseous water
posted by Existential Dread at 7:01 PM on February 13

yawn... call me when the collective behaviour of moshers resembles a 3D gas.
posted by piyushnz at 7:17 PM on February 13 [3 favorites]

This model kind of gave me the creeps. I really hate moshpits.
posted by Existential Dread at 7:23 PM on February 13 [1 favorite]

Back in my salad eating days, when I was skinny and had cool hair, I was once informed by a glorious young woman, at some set or another at all-ages La Luna, that I was an excellent mosher. Missing you, 90's!
posted by Brocktoon at 7:31 PM on February 13 [3 favorites]

Is this really 'emergent' behavior, since most mosh pits have rules that are either unspoken

If the rules are unspoken, they're almost by definition emergent behavior.
posted by empath at 7:32 PM on February 13

And when the music gets below a certain tempo, the moshers phase into a Bose-Einstein-Emerson-Lake-Palmer condensate.
posted by RobotVoodooPower at 7:47 PM on February 13 [7 favorites]

Back in my college days I used to go to dirt-cheap punk shows at a now-defunct venue a few blocks from my dorms at the University of Pittsburgh. Eight bucks for some local kids, maybe twelve for a big-name act like the Bouncing Souls.

Now, I've always been a skinny kid; back then I was downright scrawny. So I'd steer clear of the moshing, as best I could; I liked the kinetic glee but not the actual injury. But one time, the pit formed up right in front of me, and I was caught on the edge - and some movement of the crowd, some surge, knocked the wind right out of me and bowled me over. I fell backwards and thought, oh fuck, I'm falling back and there's stomping and kicking and I'm going to get very, very badly hurt. Oh fuck. Oh fuck.

But I didn't. I didn't even go over forty-five degrees as I fell backwards. Because despite the chaos and the shouting and the dim lights and the epic god-shattering sound of the band, the crowd was aware. It knew what it was doing. And four separate sets of arms darted out of the crowd and grabbed me, steadied me, brought me unharmed back to my feet. It was like the crowd, in its eagerness to revel in havoc and chaos, knew that accidental harm would break the spell that makes the pit so powerful, and it acted through its constituent parts to ensure I was unhurt.

I am not a religious man; I am as far as anyone I have ever met from superstition and mysticism. So I know that the crowd doesn't really literally think for itself. But that's what it felt like, and the emergence of order from chaos is a beautiful, magical thing to experience first hand. It is as close as I can get, I think, to approximating how faith must seem to those that feel it. I tripped and lost my footing, but I remained unharmed, because my punk rock brothers and sisters would not let me fall.
posted by Tomorrowful at 8:49 PM on February 13 [19 favorites]

I am not a religious man; I am as far as anyone I have ever met from superstition and mysticism. So I know that the crowd doesn't really literally think for itself. But that's what it felt like, and the emergence of order from chaos is a beautiful, magical thing to experience first hand. It is as close as I can get, I think, to approximating how faith must seem to those that feel it. I tripped and lost my footing, but I remained unharmed, because my punk rock brothers and sisters would not let me fall.

This is normally where I would quote a Hold Steady song, but they're pretty much all about this. Except for the ones about 'skins in the pit' and people getting stabbed or beat up in the pit are associated with a loss of faith.
posted by Charlemagne In Sweatpants at 8:53 PM on February 13

Next from MIT Technology Review: Projectile Vomiting After Intense Partying.

Wherein the equation
x = x₀ + v₀xt + ½axt²
is derived.
posted by twoleftfeet at 9:58 PM on February 13

Apropos of nothing, I've just noticed that the Wikipedia page on vomiting prefaces with the phrases "Vomit" redirects here. "Heaving" redirects here."Puke" redirects here. Which makes me not want to touch that page.
posted by twoleftfeet at 10:07 PM on February 13

actually, this is not news...all crowd behaviour exhibits gas characteristics (the collisions happen at the boundaries of 'personal space' not actual physical contact like in a mosh pit)...what happens in a MOB and what makes them so dangerous is that humans undergo an actual phase change and become liquid...it's scarier than you can possibly imagine, and if you've ever been unfortunate enough to be in a mob, it's an experience you'll NEVER forget. Ever noticed those waist-high poles near the exits of stadiums and other large venues? Those aren't to keep traffic off the sidewalk...they're specifically to break up mobs and return folks to their natural gas state.
posted by sexyrobot at 12:45 AM on February 14 [3 favorites]

So what molecules are these?

1.) The 300 pound skinhead with his little head-kicking buddy on his shoulders

Bromomethanesulfonyl bromide.

2.) The guy who knocks LittleSkinhead off BigSkinhead, sending them both careening william and nilliam

Sodium Ethoxide.

3.) The brodawgs who just show up start pushing people into each other and then bitch and pout when people tell them to knock it off

Potassium Dichromate.

4.) The one really sweaty shirtless guy who hugs everyone and is apparently On Something (HE LOVES YOU MAN)

Phenol.

5.) The dude with the green mohawk that is basically one horn that is secretly awesome and taking care of everyone

Nitrogen or Argon depending on the size of the mohawk and what shade of green it is.

6.) The yahoo with the dreadlocks and the striped stocking cap who thinks people are going to catch him when he stage dives

2,4,6-tribromophenol.

7.) The itty bitty teeny weeny nerdy metal chick whose feet never touch the floor the entire show

Helium.

8.) The drunk who pulls a girl's pants off

Free radical Oxygen.

9.) The five guys who throw the asshole out because where the fuck is security seriously

R)-3,4-dihydroxy-5-((S)- 1,2-dihydroxyethyl)furan-2(5H)-one

10.) The singer who jumps offstage to help throw the asshole out

N-isopropyl-N'-phenyl-p-phenylenediamine

posted by Kid Charlemagne at 12:56 AM on February 14 [10 favorites]

Goths used to dance in circles (and may still do) but it was mostly about protecting the handbags.
posted by Mezentian at 1:39 AM on February 14 [3 favorites]

> This model kind of gave me the creeps. I really hate moshpits.

That's fun to play with. If you turn flock strength and speed all the way up, you get little roving gangs of moshers bashing their way through the crowd.
posted by lucidium at 3:26 AM on February 14

I knew someone would have answers for me. God, I love Metafilter.

yawn... call me when the collective behaviour of moshers resembles a 3D gas.


Though there wasn't any moshing, per se, but at the last Neurosis show someone dropped some ass that was 3D, visible, and probably sentient. You would have been VERY impressed.

No, I did not "smel't" it. The odor was preceded by screaming. Like I said, impressive.
posted by louche mustachio at 7:00 AM on February 14 [1 favorite]

"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,” say Jesse Silverberg and pals at Cornell University in Ithaca."

Uh, grindcore keeps getting faster, but I don't think it's hit freakin’ 350 bpm yet, unless they're saying that the notes in a blast beat are eighth notes instead of sixteenths. If so, I'd argue that's not how it is commonly perceived and likely not how it feels to the rest of the band.
posted by ignignokt at 7:39 AM on February 14

Emergence is seriously cool.
posted by stonepharisee at 11:00 AM on February 14 [1 favorite]

Though there wasn't any moshing, per se, but at the last Neurosis show someone dropped some ass that was 3D, visible, and probably sentient. You would have been VERY impressed.

the browneye of every storm

i'm sorry, that was terrible
posted by FatherDagon at 12:47 PM on February 14

I knew someone would have answers for me. God, I love Metafilter.

Glad to be of service.
posted by Kid Charlemagne at 1:12 PM on February 14