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Emergence of collective oscillations in human crowds

nature.com

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Re: Emergence of collective oscillations in human crowds

#2
Crowds of a high enough density push people in orbital waves, with both clockwise and counterclockwise oscillations pulsing at 18 second intervals through the crowd. Monitoring these motions in realtime is possible and may help prevent crowd crush events. Also: At high densities crowds act like sticky springs, with the ground adding the sticky.

18 seconds before the next wave of people crushes you. 18 seconds to get out. 18 seconds could save your life.

Re: Emergence of collective oscillations in human crowds

#3

Crowds of a high enough density push people in orbital waves, with both clockwise and counterclockwise oscillations pulsing at 18 second intervals through the crowd. Monitoring these motions in realtime is possible and may help prevent crowd crush events. Also: At high densities crowds act like sticky springs, with the ground adding the sticky. 18 seconds before the next wave of people crushes you. 18 seconds to get…

I like your summary. Thanks!

Re: Emergence of collective oscillations in human crowds

#5

Crowds of a high enough density push people in orbital waves, with both clockwise and counterclockwise oscillations pulsing at 18 second intervals through the crowd. Monitoring these motions in realtime is possible and may help prevent crowd crush events. Also: At high densities crowds act like sticky springs, with the ground adding the sticky. 18 seconds before the next wave of people crushes you. 18 seconds to get…

Beautiful. Thank you.

Re: Emergence of collective oscillations in human crowds

#6

Crowds of a high enough density push people in orbital waves, with both clockwise and counterclockwise oscillations pulsing at 18 second intervals through the crowd. Monitoring these motions in realtime is possible and may help prevent crowd crush events. Also: At high densities crowds act like sticky springs, with the ground adding the sticky. 18 seconds before the next wave of people crushes you. 18 seconds to get…

Two things that would deserve clarification (although outside of the scope of the research here) are:

(1) When is it time to leave? At what threshold? Is it around an arm's length of free space between people?

And (2) Where to go? Straight line towards an exit? Perpendicular to the crowd? Exactly against the flow? Along the flow but towards edges? Probably depends on a lot of parameters..

Re: Emergence of collective oscillations in human crowds

#8
Interesting work! It is interesting how a lot of the models in physics and outside of it comes down to variations of harmonic oscillators (in this case macroscopic chiral oscillators). I am curious is the chirality gets imposed by the location and the architecture. Another interesting bit to explore would be how the agency (in my head agency is loosely defined as the number of possible actions you can take) of each individual gets contained as the crowd gets dense. If there is a way to define agency mathematically, it would be interesting to look at the correlation between agency and crowd density (my guess is inverse correlation) and then come up with strategies to increase the agency.

Re: Emergence of collective oscillations in human crowds

#9
post #6

Crowds of a high enough density push people in orbital waves, with both clockwise and counterclockwise oscillations pulsing at 18 second intervals through the crowd. Monitoring these motions in realtime is possible and may help prevent crowd crush events. Also: At high densities crowds act like sticky springs, with the ground adding the sticky. 18 seconds before the next wave of people crushes you. 18 seconds to get…

Two things that would deserve clarification (although outside of the scope of the research here) are: (1) When is it time to leave? At what threshold? Is it around an arm's length of free space between people? And (2) Where to go? Straight line towards an exit? Perpendicular to the crowd? Exactly against the flow? Along the flow but towards edges? Probably depends on a lot of parameters..

I don’t recall where, but for some reason I remember learning that if people start to bump into you too many times, that’s a warning shot to get out. It was something like “bumps per second”.
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