Elections are complicated stuff: a bunch of people decide on what to do, a number of factors playing in. It looks pretty much impossible to understand physically.

Sure, nobody knows what goes through everyone else’s mind, but it’s possible to figure out some society-scale stuff. The principle is similar to teasing out values like air temperature and pressure in a room, without the need to track each air molecule as it goes about its business.
Indeed, physicists used an enormous playbook of models to tease out a bunch of details about society-scale stuff, from voter turnout to candidate performance. It all starts from how we make decisions, and the simplest way to look at it is magnets. Yup, magnets.

How magnets pick their poles is a staple of statistical physics. We model them a number of spins, tiny magnetic compass needles, that point up or down—vote democrat or republican, if you will. They each have a small magnetic field, and they all influence each other, trying to align to their neighbors or getting their neighbors to align with them. Likewise, our friends, relatives, and acquaintances occasionally convince us of their arguments, just as we convince them.
Of course, decision-making is immensely more complicated than that—magnetism is more involved too, by the way. Nevertheless, we can single out the effect of different factors, like the impact of social media.

Facebook (far from being the only one) selectively presents us with voices we agree with, tuning out the rest. In magnetism terms, it’s as if spins could sever ties with neighbors pointing the opposite way. The effect? It’s easier to form bunches of aligned spins, in which no-one knows anyone that votes Trump. Society becomes polarized. Sounds familiar?

This is a very simplified example (of a simple effect, for that matter). However, it shows that models can single out different effects. Therefore, they also show what knobs to turn to shift the election climate and the tone of the discourse one way or the other.
Obviously, we haven’t solved human behavior: it is very important to keep in mind that these are super-simplified models, and that a number of things factor into real-life elections. But if social and physical sciences talk, they will get better and better insights.
Meanwhile, go vote.
If you want more
- Yes, everyone is a marvelous, unique snowflake that decides on their own. Except when they don’t: Asch’s conformity experiment and suicidally conformist ants
- In a recent post on a CalTech blog there’s a more technical take on voting and magnets
