Entropy signatures of interstate aggression on social cohesion dynamics

This study proposes a systems approach to explore the entropy signatures of war phaseson social cohesion dynamics in Ukraine (2004-2025). Using a psycholinguistic time series ofonline searches for first-person plural pronouns, we quantified social cohesion complexity usingsample entropy and refined composite multiscale entropy (RCMSE). Analyses reveal distinctsignatures between war phases over time for both metrics, with respectively R2 = 0.57and R2 = 0.95. Relative to peace and full invasion, social cohesion entropy decreased underpartial invasion and displayed more anti-persistent behavior. While social cohesion was mostdysfunctional under partial invasion, entropy signatures of full-scale invasion and peace wererelatively close. These results offer insights into the impact of interstate aggression on socialcohesion and contribute to a thermodynamic understanding of warfare as a systemic shock.The methodology provides a framework for monitoring and predicting societal resilience inresponse to significant events.