Overview
- Laurent Pujo-Menjouet released Love! Valour! Equations! in English on Monday, laying out a model that treats the rate of change of a partner's feeling P'(t) as driven by erosion, discrete life events, partner reaction and a critical breakup threshold.
- The model explicitly names terms: E for habituation-driven erosion, g(tk) for positive or negative life events like childbirth or infidelity, R(t) for a partner's response, and M as a threshold below which feelings collapse toward separation.
- Mathematician Rebecca Tyson, writing in the book's foreword, says formal models can yield useful insights but warns that human social behavior is too complex to be fully captured by any single mathematical framework.
- Clinicians and relationship researchers voiced caution, arguing individual trajectories resist reliable prediction in practice and pointing to moment-to-moment shifts, structural factors and alternatives as major drivers of outcomes.
- Therapists cited established behavioral methods such as the Gottmans' observational work and simple signs like kissing as empirically useful predictors, while demographers noted wider forces—education, religion and local conditions, with Germany's average marriage length around 14 years—shape relationship lifespans.