Experimental verification of a dissipative self-organized sandpile

Abstract

Self Organized Criticality (SOC) has long been hypothesized to be present only in conservative systems. Recently, Juanico, Monterola and Saloma, in a series of seminal articles, demonstrated using branching process theory that dissipative systems can in fact exhibit SOC. Here, we demonstrate an experimental verification of such claims and support the finding using a cellular automata model. In contrast with a static sandpile model where gradually adding grains sustain the criticality, our set-up consists of sandpiles whose population logarithmically decays as a result of horizontal vibration. Consistent with existing data on earthquake-triggered landslides, the scaled set-up used here recovered the power exponent α = −3/2 which is indicative of true criticality. Rather than maintaining the grains at critical state, correlated slope failures in our set-up result from external vibrations and/or simulated rainfall, and hence is closer to natural processes.