Wild swings of beliefs — physics and sociology

Linas Vepstas
3 min readMay 10, 2018

We are all hyper-aware of political polarization these days. But what is the cause, how can it be explained? One model is the so-called “echo chamber”, where you only hear the opinions similar to your own. In the old days (centuries ago) we’d say “birds of a feather flock together”. Sure, social media has a way of amplifying the echoes. Sure, the algorithms at FB, g+, etc. artificially boost the echoes.

Another model is the “infectious disease” model — that thoughts and beliefs spread from person to person, by contact. This is a mathematically interesting model, as it explicitly represents contacts as a graph — a large, network graph — with things happening, things moving along the edges, and so one can actually construct mathematical and computational, algorithmic models of social reality, and try to understand that sociological reality in this way.

How infectious is it? I’ve watched two social-media acquaintances/regulars (almost “friends”) go “crazy”, viz. suddenly started spouting false/fake memes (alt-right in both cases) — memes, concepts, generalizations that are just obviously false, plainly incorrect, distorted, over the top. They became openly hostile to anyone who tried to talk sense to them — “rabid”, one could say, attacking friends. Bother were well-above-average IQ, so its not an ordinary case of “gullibility” of the weak-minded. Its as if being smart was an important ingredient for synthesizing lots of disparate “evidence” into their new, crazy viewpoints. (And yes, they cited lots of “evidence”.)

Its not just on the right — I have a friend who has been a crazy leftist since his teen-age years. I just roll my eyes when he says outrageous things. Perhaps I’m more tolerant of crazy-left than crazy-right. On the other hand, I also have close family and friends who hold unabashedly racist beliefs. So it goes. It doesn’t have to be about politics. It can be about flat-earth, moon-landing hoax-conspiracy, chem-trails, or Jennifer Aniston’s current boyfriend. Which brings me to the next model: in physics, the approach of system to a (second-order) phase transition.

The boiling of water, and conversely, the condensation of steam into droplets is an example of a (first-order) phase transition. Let me ignore the first/second-order thing for now. A characteristic of such phase transitions is that the scale, the variation of sizes blows up. In rain, raindrops of various sizes; in boiling water, bubbles of various sizes — including some huge ones.

If social media is pushing is towards a phase transition, then the wildness, the swings increase, not decrease. Again — not just in politics, but also beliefs in flat earth — all of these get wilder and more out-of-hand, more out-of-control, as social media allows more and more “evidence” to flow from one mind to another, causing normally placid, calm, detached people to change their opinions more frequently, more dramatically, more forcefully. Simply being bombarded by all these “facts”, all this on-line “evidence” is tearing down and rebuilding people’s belief systems rapidly — and not necessarily towards more agreement, but perhaps towards more disagreement.

Note that some network models exhibit phase transitions.

The end. This post does not have a point. Sorry for the let-down. It doesn’t say anything that hasn’t been said before. It does repeat and popularize certain ideas. I think the insights are useful, and can be applied by sociologists (and are, by applied sociologists). I think they also indicate a way for machine intelligence to come into contact with social reality. Which is one of my interests.