Black swans, dragon-kings, and the power of predictability

New Scientist : A group of researchers is working on a method to predict extreme events or catastrophes in order to prevent them from happening. Their research centers on a certain class of catastrophic event, named a “dragon-king” by Didier Sornette of ETH Zürich. Unlike a “black swan"—another type of catastrophe, which occurs unexpectedly but follows the power law that says the bigger the event the less likely it is to occur—a dragon-king is a catastrophic event so big that it should be rare, but it isn’t. Examples include cracks that develop on spacecraft, massive rainstorms, financial crashes, and epileptic seizures. To better understand such events, the researchers studied chaotic oscillators that, when paired, synchronize most of the time. The researchers found that not only could they predict when the two oscillators would get out of sync but they could prevent the desynchronization by applying an electrical voltage at just the right moment. The researchers claim that it may one day be possible to identify the mechanisms leading up to such catastrophes and, by applying tiny perturbations to the system, avert a disaster.