Field notes

A meme spreads like an epidemic. Each account that shares it exposes its neighbours; some of them share too, and the thing climbs exponentially — "each share recruits more sharers." But every account that shares it eventually tires of it and goes dark: overexposed, cringe, normie-fied. That fatigue is the meme's undoing. The same popularity that spreads it is exactly what kills it.

This is an SIRS-with-strains model. Each account is Susceptible, Infectious (sharing), or Recovered (fatigued). A sharer burns out at rate gamma; fatigue then wanes slowly, so a stale format eventually feels fresh again. Crank catchiness and the meme floods the whole network at once — which dooms it, because everyone burns out together. Throttle it and a niche meme smolders far longer without ever saturating.

Turn up mutation and each share can spawn a remix — a copy carried far enough in "genome space" that the fatigue built against the original barely blocks it (cross-immunity X=exp(-|Δg|/λ)). Most remixes die in a handful of accounts. But once in a while, after the original is dead, a lucky variant finds freshly-tired accounts it can still infect and rides a genuine second wave — a dead format resurrected as something new.

Simplifications: "fatigue" stands in for cringe / normie-fication; "immunity waning" for a format going stale enough that a remix reads as fresh. Accounts are identical — the network topology and the two dials do all the work. This is a model of contagion, not of humour or taste.