A new study has revealed that the propagation of contagion phenomena in complex networks, such as diseases or information, does not follow a random structure, but is organized into a temporal "backbone." This structure, which persists over time, determines the effectiveness and speed with which a contagion spreads, offering a new perspective on propagation dynamics in complex systems. The discovery challenges previous models that assumed homogeneity or randomness in interactions, highlighting the importance of the temporal sequence of contacts.

The researchers used a novel approach to analyze temporal networks, where connections between nodes (individuals, computers, etc.) are not static, but appear and disappear at specific moments. By applying this method to various datasets, from social interactions to the spread of computer viruses, they identified recurrent patterns in the sequence of contacts that act as preferential channels for transmission. These channels form the aforementioned backbone, which is denser and more persistent than the rest of the network.

The identification of this temporal backbone allows for better prediction of a contagion's trajectory and, potentially, the design of more effective intervention strategies. For example, by understanding which sequences of contacts are crucial for propagation, containment efforts could be focused on those specific points, rather than applying indiscriminate measures. This has direct implications in epidemiology, cybersecurity, and information dissemination, paving the way for more precise predictive models and the optimization of control strategies.