AP News: Experts - In huge crowds like that of the hajj, lethal conditions can build up quickly
"It's largely a physical phenomenon, not a psychological one," Professor Dirk Helbing said for the prominent news agency AP.
The Associated Press (AP) - one of the most influential news agencies in the world - quoted Professor Dirk Helbing. external pageThe article was published in AP in September 2015 and was republished in many other newspapers. Dirk Helbing is a professor at ETH Zurich.
"When too many people are squeezed into too small a space, the situation can turn dangerous very quickly, experts say. And that, they say, may be key to understanding the deaths of more than 700 pilgrims on the outskirts of Mecca. 'It's largely a physical phenomenon, not a psychological one,' says Dirk Helbing, a professor of computational social science at ETH Zurich, who has studied crowds and disasters. When the density is too high, movements of a body 'transfers forces to other bodies. These forces can add up and create uncontrollable movements in the crowd. So 'a small problem turns into a big problem that is not controllable anymore,' Helbing said. A large crowd can 'get out of control very quickly.'"