The Hungarian physicist Tamas Vicsek, from the Eötvös University in Budapest, has studied the evolution of
social relationships by analyzing a network of 30,000 individuals and the contact lists of the mobile phones of 4 million users. Putting together the data, he has come to the conclusion that
large groups persist longer if their members are renewed. "The ability to change the composition of large groups implies greater
adaptability, " says the researcher. On the contrary, he has shown that
small groups tend to be more
stable , and that only if the relationships between their members are lasting does the group remain together for a long time.
With these results, Vicsek has developed a mathematical formula that allows predicting whether an individual will remain in a group or leave it.
This physicist, an expert in modeling social behavior, has also put numbers to some crowd behavior patterns, such as creating a " wave " in the audience of a sporting event . As Vicsek concluded a few years ago, a minimum of people is required to start the wave, specifically 30, and generally the wave circulates in a clockwise direction and advances at 12 meters per second (20 seats).
Tamas Vicsek website (http://angel.elte.hu/~vicsek/)
