Physics

Mathematical model reveals potential pathways to global population crisis

AI Insight

Researchers have developed a nonlinear differential equation that mathematically models global population growth over the past 12,000 years, unifying previously separate models including Malthusian exponential growth, logistic growth, and von Foerster's doomsday predictions as special cases of the same general equation. The model demonstrates that earlier approaches were only valid for limited time periods because they neglected higher-order terms in the complete dynamics. Under a conservative worst-case scenario where carrying-capacity constraints become immediately active, the model predicts global population could decline to half its current level by 2064.


This unified mathematical framework could improve long-term demographic forecasting and help policymakers better understand potential population trajectory risks. The model's prediction of possible rapid population decline highlights the importance of considering resource constraints and sustainability in global planning.


arXiv:2502.19063v5 Announce Type: replace-cross
Abstract: We show that a simple nonlinear differential equation (originally studied in the physics of disordered systems) is able to mathematically describe the global population growth over the past 12000 years. Different regimes of population growth since the early Neolithic until today are shown to be all solutions to the same nonlinear differential equation in its various limits. These also include the well-known Malthus (exponential) and Verhulst (logistic) growth regimes, as well as von Foerster’s “doomsday” formula. All these limits correspond to neglecting higher-order terms in a more general nonlinear dynamic model described by the proposed nonlinear differential equation. While the older models may provide valid fittings to limited time intervals in the global population growth curve in time, their clearly approximate nature prevents them from being predictive over longer periods of time. The proposed comprehensive solution of the proposed model is instead well suited to provide predictions for future scenarios. These include a scenario where the global population could halve as early as 2064 under a deliberately conservative, worst-case assumption that carrying-capacity constraints become abruptly active today.

Source: Global population crisis scenarios predicted by a general nonlinear dynamical model