Self-organised-criticality and punctuated equilibrium in bouncing balls

A nonlinearly coupled system of bouncing balls is shown to exhibit features like self-organised-criticality (SOC) and punctuated equilibrium (PE) in suitable parameter domains. The temporal evolution of the non-stationary amplitudes is analysed through local methods to unravel the transient periodic components and fluctuations giving rise to SOC and PE type behaviours. This simple dynamical system follows Gutenberg-Richter relation and also manifests the Devil's staircase, explicating the universality of these features in diverse complex systems.