A new study has warned that the global population could be halved by 2064. The prediction, based on a mathematical model, is not a forecast but an "illustrative mathematical scenario" showing how sudden changes can impact population dynamics.

The researchers, including Alessio Zaccone of the University of Milan and his late colleague Kostya Trachenko, who worked at Queen Mary University in London, examined 12,000 years of human growth and created an equation that accurately reflected these trends.