Terrorism as a Self-Organised Criticality Phenomenon

An examination of the heuristic capabilities of the self-organized criticality (SOC) theory for studying social processes, reviewing key ideas of the theory and the methods of identifying pink noise as an SOC attribute. The authors analyze terrorism in twenty countries in the period from 1970s to 2014. The source of the background data is the Global Terrorism Database, maintained by the START Consortium. SOC approaches and methodology were used to identify and explain such non-linear effects as spontaneous outbreaks of terrorism. It is found that numerical series that reflect changes in the terrorism volume are essentially pink noise. This allowed the universal explanatory schemes of SOC theory to be applied to interpret such systems features and dynamics and demonstrate that in many countries, terrorism is a self-organized criticality phenomenon. Systems in the state of SOC are capable of abrupt growth in activity without any apparent reason. One of the parameters of the numerical series studied ‒ power-law exponent ‒ can serve as an indicator of the internal state of the societies prone to terror threats.