The future belongs to crowds.
— Don DeLillo, Mao II
Iâ€™m spending a lot of time thinking about crowds and crowd turbulence, of late. In a presentation today, I used the the following photo from a paper on crowd turbulence as evidenced by pilgrims crossing a bridge in Saudi Arabia. The blurred areas in the time-lapse photo represent areas of the crowd where turbulence has set in.
When conditions become congested, the flow drops significantly, which can cause stop-and-go waves and a further increase of the density until critical crowd conditions are reached. Then, â€œcrowd
turbulenceâ€ sets in, which may trigger crowd disasters.
— Source: From Crowd Dynamics to Crowd Safety (arXiv 2008)