A Network That Decides When to Stop express

Original: "Feedback percolation on complex networks"
arXiv:2603.22089 · 2026-03-23 · CC BY 4.0 · 1 min
An ordinary network can suddenly explode in growth or get stuck in a loop if its size influences every new connection.

A Network That Decides When to Stop

A crowd grows: each new person joins the group with a probability that depends on how large the group already is. If the group is small, joining is easy; if it is huge, people start to hesitate, and growth slows down. This mechanism, called feedback, changes the entire behavior of the network.

In classical percolation theory, the probability of joining is always constant, like a fixed ticket price for a concert. Here, the price rises with the number of spectators, and the hall either fills up instantly or pulsates, opening and closing its doors.

The researchers added this loop to a mathematical model and saw a surprising diversity: the network can explode in a jump, transition smoothly to a new state, then oscillate like a pendulum, or even descend into chaos. Such regimes resemble the behavior of real systems — from power grid overloads to the spread of epidemics.

The work shows that macroscopic order can govern microscopic rules, and this is a general principle for self-regulating systems. Now we can better predict when infrastructure will hold steady and when it will collapse in an avalanche.

Oscillations in the size of the giant component in such a network resemble economic cycles: boom gives way to bust, but without external intervention — only due to internal rules.

This approach brings together disparate phenomena under one roof and provides a tool for analyzing complex networks where the whole influences the parts.

In the feedback model, a network can behave like a predator and prey: the size of the giant component grows, then falls, and the cycle repeats endlessly, even though no external forces intervene.

In Stanislaw Lem's novel 'Solaris', the planet-ocean self-regulates through feedback, generating unexpected structures — similar to networks that change their own growth rules.

Scientists
Andrey Markov
Concepts
feedback loop positive feedback loop control theory emergent complexity modeling complex systems complex system dynamics network collective behavior Neural Network Oscillations mixed mode oscillations probabilistic model stochastic self organization quantum collective phenomena classical physics power law distribution nonlinear interaction ecosystem stimulus perturbation theory game theory