I can choose science

The physics of elections - phase changes explain extreme politicians

Cambridge (USA) - Physics cannot only describe the behavior of black holes, shining lasers or falling apples. Social processes in which a large number of people are involved also show parallels to physical descriptions of systems made up of a large number of particles. For example, the development of a traffic jam can be described with the help of thermodynamics. Now American physicists even found analogies between the outcome of elections and magnetic systems. In the journal "Nature Physics" they are increasingly comparing extreme elective outcomes with an unstable, physical system in the vicinity of a phase change.

Alex Siegenfeld and Yaneer Bar-Yam of the Massachusetts Institute of Technology and the New England Complex Systems Institute (NECSI) looked at the rise in extreme opinion among the electorate for their analysis. This polarization means that a low turnout makes it possible for politicians with fundamentally different opinions to be elected. The researchers see an example in the change from Democratic President Barack Obama to Republican Donald Trump. Siegenfeld and Bar-Yam explain this elective outcome with a magnetic system in the vicinity of a phase change: Even small changes in external boundary conditions lead to a fundamental change in the physical properties of the system.

According to the researchers, such unstable conditions - caused by strongly polarized opinions in the electorate - are largely responsible for drastic changes in elections. In addition, after a drastic change in policy, around half of the electorate do not feel represented by the elected political leader. An effect that could further strengthen the polarization of society.

Based on their physical model, the researchers took a closer look at the American presidential election since World War II. "In 1970 there was a phase change and the elections went from stable to unstable," says Yaneer Bar-Yam. With Roosevelt, Eisenhower or Kennedy - regardless of party affiliation - candidates with more balanced convictions were chosen. But from 1970 instability increased, which led from Reagan to Bush and Clinton to Obama and Trump to presidents with more polarized views. According to the researchers, a greater turnout could help counter this development. "If candidates can rely on many voters, future elections will be more stable again," says Siegenfeld. "With a high turnout, not only are more voter opinions represented, but it also results in long-term stability of democracy."

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