# Why hipsters all look alike

Jonathan Touboul is a mathematician and a neuroscientist. He holds a PhD in math from France’s prestigious École Polytechnique, where he won a prize for his thesis on how to simulate neurons in the brain. He publishes papers with titles like “Pulsatile localized dynamics in delayed neural-field equations in arbitrary dimension” and “The propagation of chaos in neural fields.”

In recent years, though, Touboul has been thinking about hipsters. Specifically, why hipsters all seem to dress alike. In his line of work, there are neurons that also behave like hipsters. They fire when every neuron around them is quiet; or they fall silent when every neuron around them is chattering.

Because he is a mathematician, Touboul began to look for a way to explore this idea using equations. In other words, he constructed a mathematical model. His key insight is that people (and neurons) do not instantly perceive what is mainstream. There’s a delay. And in situations where the delay is large enough, the contrarians can inadvertently synchronize with each other.

“In wanting to oppose the trends, there actually emerges some sort of hipster loop,” Touboul said.

A day before Halloween, Touboul put a draft of his paper on the arXiv, calling it “The hipster effect: When anticonformists all look the same.